[REF] web: move some code from pyeval to lib py_extras

Some functions that were in web.pyeval were actually "odoo independant".
To make them easier to manage/understand, this commit move them in the
library py.js, as an extra file.

4 files changed, 801 insertions, 761 deletions

diff --git a/addons/web/static/lib/py.js/lib/py_extras.js b/addons/web/static/lib/py.js/lib/py_extras.js
new file mode 100644
index 00000000000..2bc69ece598
--- /dev/null
+++ b/addons/web/static/lib/py.js/lib/py_extras.js
@@ -0,0 +1,784 @@
+(function (py) {
+"use strict";
+
+/**
+ * This file add extra functionality to the python interpreter exported by py.js
+ *
+ * Main extra functionality is about time management, more precisely:
+ * - date
+ * - datetime
+ * - relativedelta
+ *
+ * These python modules are exported in the py.extras object, and can be added
+ * to the evaluation context.  For example,
+ *
+ *  var context = {
+ *      datetime: py.extras.datetime,
+ *      date: py.extras.date,
+ *      time: py.extras.time,
+ *  };
+ *  var result = py.eval(some_python_expression, context);
+ */
+
+/*
+ * py.js helpers and setup
+ */
+
+/**
+ * computes (Math.floor(a/b), a%b and passes that to the callback.
+ *
+ * returns the callback's result
+ */
+function divmod (a, b, fn) {
+    var mod = a%b;
+    // in python, sign(a % b) === sign(b). Not in JS. If wrong side, add a
+    // round of b
+    if (mod > 0 && b < 0 || mod < 0 && b > 0) {
+        mod += b;
+    }
+    return fn(Math.floor(a/b), mod);
+}
+
+/**
+ * Passes the fractional and integer parts of x to the callback, returns
+ * the callback's result
+ */
+function modf(x, fn) {
+    var mod = x%1;
+    if (mod < 0) {
+        mod += 1;
+    }
+    return fn(mod, Math.floor(x));
+}
+
+function assert(bool) {
+    if (!bool) {
+        throw new Error("AssertionError");
+    }
+}
+
+
+var obj = function () {};
+obj.prototype = py.object;
+var asJS = function (arg) {
+    if (arg instanceof obj) {
+        return arg.toJSON();
+    }
+    return arg;
+};
+
+var datetime = py.PY_call(py.object);
+
+var zero = py.float.fromJSON(0);
+
+// Port from pypy/lib_pypy/datetime.py
+var DAYS_IN_MONTH = [null, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
+var DAYS_BEFORE_MONTH = [null];
+var dbm = 0;
+
+for (var i=1; i<DAYS_IN_MONTH.length; ++i) {
+    DAYS_BEFORE_MONTH.push(dbm);
+    dbm += DAYS_IN_MONTH[i];
+}
+
+function is_leap(year) {
+    return year % 4 === 0 && (year % 100 !== 0 || year % 400 === 0);
+}
+
+function days_before_year(year) {
+    var y = year - 1;
+    return y*365 + Math.floor(y/4) - Math.floor(y/100) + Math.floor(y/400);
+}
+
+function days_in_month(year, month) {
+    if (month === 2 && is_leap(year)) {
+        return 29;
+    }
+    return DAYS_IN_MONTH[month];
+}
+
+function days_before_month(year, month) {
+    var post_leap_feb = month > 2 && is_leap(year);
+    return DAYS_BEFORE_MONTH[month] + (post_leap_feb ? 1 : 0);
+}
+
+function ymd2ord(year, month, day) {
+    var dim = days_in_month(year, month);
+    if (!(1 <= day && day <= dim)) {
+        throw new Error("ValueError: day must be in 1.." + dim);
+    }
+    return days_before_year(year) +
+           days_before_month(year, month) +
+           day;
+}
+
+var DI400Y = days_before_year(401);
+var DI100Y = days_before_year(101);
+var DI4Y = days_before_year(5);
+
+function ord2ymd(n) {
+    --n;
+    var n400, n100, n4, n1, n0;
+    divmod(n, DI400Y, function (_n400, n) {
+        n400 = _n400;
+        divmod(n, DI100Y, function (_n100, n) {
+            n100 = _n100;
+            divmod(n, DI4Y, function (_n4, n) {
+                n4 = _n4;
+                divmod(n, 365, function (_n1, n) {
+                    n1 = _n1;
+                    n0 = n;
+                });
+            });
+        });
+    });
+
+    n = n0;
+    var year = n400 * 400 + 1 + n100 * 100 + n4 * 4 + n1;
+    if (n1 == 4 || n100 == 100) {
+        assert(n0 === 0);
+        return {
+            year: year - 1,
+            month: 12,
+            day: 31
+        };
+    }
+
+    var leapyear = n1 === 3 && (n4 !== 24 || n100 == 3);
+    assert(leapyear == is_leap(year));
+    var month = (n + 50) >> 5;
+    var preceding = DAYS_BEFORE_MONTH[month] + ((month > 2 && leapyear) ? 1 : 0);
+    if (preceding > n) {
+        --month;
+        preceding -= DAYS_IN_MONTH[month] + ((month === 2 && leapyear) ? 1 : 0);
+    }
+    n -= preceding;
+    return {
+        year: year,
+        month: month,
+        day: n+1
+    };
+}
+
+/**
+ * Converts the stuff passed in into a valid date, applying overflows as needed
+ */
+function tmxxx(year, month, day, hour, minute, second, microsecond) {
+    hour = hour || 0; minute = minute || 0; second = second || 0;
+    microsecond = microsecond || 0;
+
+    if (microsecond < 0 || microsecond > 999999) {
+        divmod(microsecond, 1000000, function (carry, ms) {
+            microsecond = ms;
+            second += carry;
+        });
+    }
+    if (second < 0 || second > 59) {
+        divmod(second, 60, function (carry, s) {
+            second = s;
+            minute += carry;
+        });
+    }
+    if (minute < 0 || minute > 59) {
+        divmod(minute, 60, function (carry, m) {
+            minute = m;
+            hour += carry;
+        });
+    }
+    if (hour < 0 || hour > 23) {
+        divmod(hour, 24, function (carry, h) {
+            hour = h;
+            day += carry;
+        });
+    }
+    // That was easy.  Now it gets muddy:  the proper range for day
+    // can't be determined without knowing the correct month and year,
+    // but if day is, e.g., plus or minus a million, the current month
+    // and year values make no sense (and may also be out of bounds
+    // themselves).
+    // Saying 12 months == 1 year should be non-controversial.
+    if (month < 1 || month > 12) {
+        divmod(month-1, 12, function (carry, m) {
+            month = m + 1;
+            year += carry;
+        });
+    }
+    // Now only day can be out of bounds (year may also be out of bounds
+    // for a datetime object, but we don't care about that here).
+    // If day is out of bounds, what to do is arguable, but at least the
+    // method here is principled and explainable.
+    var dim = days_in_month(year, month);
+    if (day < 1 || day > dim) {
+        // Move day-1 days from the first of the month.  First try to
+        // get off cheap if we're only one day out of range (adjustments
+        // for timezone alone can't be worse than that).
+        if (day === 0) {
+            --month;
+            if (month > 0) {
+                day = days_in_month(year, month);
+            } else {
+                --year; month=12; day=31;
+            }
+        } else if (day == dim + 1) {
+            ++month;
+            day = 1;
+            if (month > 12) {
+                month = 1;
+                ++year;
+            }
+        } else {
+            var r = ord2ymd(ymd2ord(year, month, 1) + (day - 1));
+            year = r.year;
+            month = r.month;
+            day = r.day;
+        }
+    }
+    return {
+        year: year,
+        month: month,
+        day: day,
+        hour: hour,
+        minute: minute,
+        second: second,
+        microsecond: microsecond
+    };
+}
+
+datetime.timedelta = py.type('timedelta', null, {
+    __init__: function () {
+        var args = py.PY_parseArgs(arguments, [
+            ['days', zero], ['seconds', zero], ['microseconds', zero],
+            ['milliseconds', zero], ['minutes', zero], ['hours', zero],
+            ['weeks', zero]
+        ]);
+
+        var d = 0, s = 0, m = 0;
+        var days = args.days.toJSON() + args.weeks.toJSON() * 7;
+        var seconds = args.seconds.toJSON()
+                    + args.minutes.toJSON() * 60
+                    + args.hours.toJSON() * 3600;
+        var microseconds = args.microseconds.toJSON()
+                         + args.milliseconds.toJSON() * 1000;
+
+        // Get rid of all fractions, and normalize s and us.
+        // Take a deep breath <wink>.
+        var daysecondsfrac = modf(days, function (dayfrac, days) {
+            d = days;
+            if (dayfrac) {
+                return modf(dayfrac * 24 * 3600, function (dsf, dsw) {
+                    s = dsw;
+                    return dsf;
+                });
+            }
+            return 0;
+        });
+
+        var secondsfrac = modf(seconds, function (sf, s) {
+            seconds = s;
+            return sf + daysecondsfrac;
+        });
+        divmod(seconds, 24*3600, function (days, seconds) {
+            d += days;
+            s += seconds;
+        });
+        // seconds isn't referenced again before redefinition
+
+        microseconds += secondsfrac * 1e6;
+        divmod(microseconds, 1000000, function (seconds, microseconds) {
+            divmod(seconds, 24*3600, function (days, seconds) {
+                d += days;
+                s += seconds;
+                m += Math.round(microseconds);
+            });
+        });
+
+        // Carrying still possible here?
+
+        this.days = d;
+        this.seconds = s;
+        this.microseconds = m;
+    },
+    __str__: function () {
+        var hh, mm, ss;
+        divmod(this.seconds, 60, function (m, s) {
+            divmod(m, 60, function (h, m) {
+                hh = h;
+                mm = m;
+                ss = s;
+            });
+        });
+        var s = _.str.sprintf("%d:%02d:%02d", hh, mm, ss);
+        if (this.days) {
+            s = _.str.sprintf("%d day%s, %s",
+                this.days,
+                (this.days != 1 && this.days != -1) ? 's' : '',
+                s);
+        }
+        if (this.microseconds) {
+            s = _.str.sprintf("%s.%06d", s, this.microseconds);
+        }
+        return py.str.fromJSON(s);
+    },
+    __eq__: function (other) {
+        if (!py.PY_isInstance(other, datetime.timedelta)) {
+            return py.False;
+        }
+
+        return (this.days === other.days
+            && this.seconds === other.seconds
+            && this.microseconds === other.microseconds)
+                ? py.True : py.False;
+    },
+    __add__: function (other) {
+        if (!py.PY_isInstance(other, datetime.timedelta)) {
+            return py.NotImplemented;
+        }
+        return py.PY_call(datetime.timedelta, [
+            py.float.fromJSON(this.days + other.days),
+            py.float.fromJSON(this.seconds + other.seconds),
+            py.float.fromJSON(this.microseconds + other.microseconds)
+        ]);
+    },
+    __radd__: function (other) { return this.__add__(other); },
+    __sub__: function (other) {
+        if (!py.PY_isInstance(other, datetime.timedelta)) {
+            return py.NotImplemented;
+        }
+        return py.PY_call(datetime.timedelta, [
+            py.float.fromJSON(this.days - other.days),
+            py.float.fromJSON(this.seconds - other.seconds),
+            py.float.fromJSON(this.microseconds - other.microseconds)
+        ]);
+    },
+    __rsub__: function (other) {
+        if (!py.PY_isInstance(other, datetime.timedelta)) {
+            return py.NotImplemented;
+        }
+        return this.__neg__().__add__(other);
+    },
+    __neg__: function () {
+        return py.PY_call(datetime.timedelta, [
+            py.float.fromJSON(-this.days),
+            py.float.fromJSON(-this.seconds),
+            py.float.fromJSON(-this.microseconds)
+        ]);
+    },
+    __pos__: function () { return this; },
+    __mul__: function (other) {
+        if (!py.PY_isInstance(other, py.float)) {
+            return py.NotImplemented;
+        }
+        var n = other.toJSON();
+        return py.PY_call(datetime.timedelta, [
+            py.float.fromJSON(this.days * n),
+            py.float.fromJSON(this.seconds * n),
+            py.float.fromJSON(this.microseconds * n)
+        ]);
+    },
+    __rmul__: function (other) { return this.__mul__(other); },
+    __div__: function (other) {
+        if (!py.PY_isInstance(other, py.float)) {
+            return py.NotImplemented;
+        }
+        var usec = ((this.days * 24 * 3600) + this.seconds) * 1000000
+                    + this.microseconds;
+        return py.PY_call(
+            datetime.timedelta, [
+                zero, zero, py.float.fromJSON(usec / other.toJSON())]);
+    },
+    __floordiv__: function (other) { return this.__div__(other); },
+    total_seconds: function () {
+        return py.float.fromJSON(
+            this.days * 86400
+          + this.seconds
+          + this.microseconds / 1000000);
+    },
+    __nonzero__: function () {
+        return (!!this.days || !!this.seconds || !!this.microseconds)
+            ? py.True
+            : py.False;
+    }
+});
+
+datetime.datetime = py.type('datetime', null, {
+    __init__: function () {
+        var zero = py.float.fromJSON(0);
+        var args = py.PY_parseArgs(arguments, [
+            'year', 'month', 'day',
+            ['hour', zero], ['minute', zero], ['second', zero],
+            ['microsecond', zero], ['tzinfo', py.None]
+        ]);
+        for(var key in args) {
+            if (!args.hasOwnProperty(key)) { continue; }
+            this[key] = asJS(args[key]);
+        }
+    },
+    replace: function () {
+        var args = py.PY_parseArgs(arguments, [
+            ['year', py.None], ['month', py.None], ['day', py.None],
+            ['hour', py.None], ['minute', py.None], ['second', py.None],
+            ['microsecond', py.None] // FIXME: tzinfo, can't use None as valid input
+        ]);
+        var params = {};
+        for(var key in args) {
+            if (!args.hasOwnProperty(key)) { continue; }
+
+            var arg = args[key];
+            params[key] = (arg === py.None ? this[key] : asJS(arg));
+        }
+        return py.PY_call(datetime.datetime, params);
+    },
+    strftime: function () {
+        var self = this;
+        var args = py.PY_parseArgs(arguments, 'format');
+        return py.str.fromJSON(args.format.toJSON()
+            .replace(/%([A-Za-z])/g, function (m, c) {
+                switch (c) {
+                case 'Y': return _.str.sprintf('%04d', self.year);
+                case 'm': return _.str.sprintf('%02d', self.month);
+                case 'd': return _.str.sprintf('%02d', self.day);
+                case 'H': return _.str.sprintf('%02d', self.hour);
+                case 'M': return _.str.sprintf('%02d', self.minute);
+                case 'S': return _.str.sprintf('%02d', self.second);
+                }
+                throw new Error('ValueError: No known conversion for ' + m);
+            }));
+    },
+    now: py.classmethod.fromJSON(function () {
+        var d = new Date();
+        return py.PY_call(datetime.datetime, [
+            d.getFullYear(), d.getMonth() + 1, d.getDate(),
+            d.getHours(), d.getMinutes(), d.getSeconds(),
+            d.getMilliseconds() * 1000]);
+    }),
+    today: py.classmethod.fromJSON(function () {
+        var dt_class = py.PY_getAttr(datetime, 'datetime');
+        return py.PY_call(py.PY_getAttr(dt_class, 'now'));
+    }),
+    utcnow: py.classmethod.fromJSON(function () {
+        var d = new Date();
+        return py.PY_call(datetime.datetime,
+            [d.getUTCFullYear(), d.getUTCMonth() + 1, d.getUTCDate(),
+             d.getUTCHours(), d.getUTCMinutes(), d.getUTCSeconds(),
+             d.getUTCMilliseconds() * 1000]);
+    }),
+    combine: py.classmethod.fromJSON(function () {
+        var args = py.PY_parseArgs(arguments, 'date time');
+        return py.PY_call(datetime.datetime, [
+            py.PY_getAttr(args.date, 'year'),
+            py.PY_getAttr(args.date, 'month'),
+            py.PY_getAttr(args.date, 'day'),
+            py.PY_getAttr(args.time, 'hour'),
+            py.PY_getAttr(args.time, 'minute'),
+            py.PY_getAttr(args.time, 'second')
+        ]);
+    }),
+    toJSON: function () {
+        return new Date(
+            this.year,
+            this.month - 1,
+            this.day,
+            this.hour,
+            this.minute,
+            this.second,
+            this.microsecond / 1000);
+    },
+    __add__: function (other) {
+        if (!py.PY_isInstance(other, datetime.timedelta)) {
+            return py.NotImplemented;
+        }
+        var s = tmxxx(this.year, this.month, this.day + other.days, this.hour, this.minute, this.second + other.seconds);
+        return datetime.datetime.fromJSON(s.year, s.month, s.day, s.hour, s.minute, s.second);
+    },
+    __sub__: function (other) {
+        if (py.PY_isInstance(other, datetime.timedelta)) {
+            return py.PY_add(this, py.PY_negative(other));
+        }
+        return py.NotImplemented;
+    },
+    fromJSON: function (year, month, day, hour, minute, second) {
+        return py.PY_call(datetime.datetime, [year, month, day, hour, minute, second]);
+    },
+});
+
+datetime.date = py.type('date', null, {
+    __init__: function () {
+        var args = py.PY_parseArgs(arguments, 'year month day');
+        this.year = asJS(args.year);
+        this.month = asJS(args.month);
+        this.day = asJS(args.day);
+    },
+    strftime: function () {
+        var self = this;
+        var args = py.PY_parseArgs(arguments, 'format');
+        return py.str.fromJSON(args.format.toJSON()
+            .replace(/%([A-Za-z])/g, function (m, c) {
+                switch (c) {
+                case 'Y': return self.year;
+                case 'm': return _.str.sprintf('%02d', self.month);
+                case 'd': return _.str.sprintf('%02d', self.day);
+                }
+                throw new Error('ValueError: No known conversion for ' + m);
+            }));
+    },
+    __eq__: function (other) {
+        return (this.year === other.year
+             && this.month === other.month
+             && this.day === other.day)
+            ? py.True : py.False;
+    },
+    replace: function () {
+        var args = py.PY_parseArgs(arguments, [
+            ['year', py.None], ['month', py.None], ['day', py.None]
+        ]);
+        var params = {};
+        for(var key in args) {
+            if (!args.hasOwnProperty(key)) { continue; }
+
+            var arg = args[key];
+            params[key] = (arg === py.None ? this[key] : asJS(arg));
+        }
+        return py.PY_call(datetime.date, params);
+    },
+    __add__: function (other) {
+        if (!py.PY_isInstance(other, datetime.timedelta)) {
+            return py.NotImplemented;
+        }
+        var s = tmxxx(this.year, this.month, this.day + other.days);
+        return datetime.date.fromJSON(s.year, s.month, s.day);
+    },
+    __radd__: function (other) { return this.__add__(other); },
+    __sub__: function (other) {
+        if (py.PY_isInstance(other, datetime.timedelta)) {
+            return py.PY_add(this, py.PY_negative(other));
+        }
+        if (py.PY_isInstance(other, datetime.date)) {
+            // FIXME: getattr and sub API methods
+            return py.PY_call(datetime.timedelta, [
+                py.PY_subtract(
+                    py.PY_call(py.PY_getAttr(this, 'toordinal')),
+                    py.PY_call(py.PY_getAttr(other, 'toordinal')))
+            ]);
+        }
+        return py.NotImplemented;
+    },
+    toordinal: function () {
+        return py.float.fromJSON(ymd2ord(this.year, this.month, this.day));
+    },
+    weekday: function () {
+        return  py.float.fromJSON((this.toordinal().toJSON()+6)%7);
+    },
+    fromJSON: function (year, month, day) {
+        return py.PY_call(datetime.date, [year, month, day]);
+    },
+    today: py.classmethod.fromJSON(function () {
+        var d = new Date ();
+        return py.PY_call(datetime.date, [
+            d.getFullYear(), d.getMonth() + 1, d.getDate()]);
+    }),
+});
+
+datetime.time = py.type('time', null, {
+    __init__: function () {
+        var zero = py.float.fromJSON(0);
+        var args = py.PY_parseArgs(arguments, [
+            ['hour', zero], ['minute', zero], ['second', zero], ['microsecond', zero],
+            ['tzinfo', py.None]
+        ]);
+
+        for(var k in args) {
+            if (!args.hasOwnProperty(k)) { continue; }
+            this[k] = asJS(args[k]);
+        }
+    }
+});
+
+var time = py.PY_call(py.object);
+time.strftime = py.PY_def.fromJSON(function () {
+    var args  = py.PY_parseArgs(arguments, 'format');
+    var dt_class = py.PY_getAttr(datetime, 'datetime');
+    var d = py.PY_call(py.PY_getAttr(dt_class, 'utcnow'));
+    return py.PY_call(py.PY_getAttr(d, 'strftime'), [args.format]);
+});
+
+var args = _.map(('year month day '
+                + 'years months weeks days '
+                + 'weekday leapdays yearday nlyearday').split(' '), function (arg) {
+    switch (arg) {
+    case 'years':case 'months':case 'days':case 'leapdays':case 'weeks':
+        return [arg, zero];
+    case 'year':case 'month':case 'day':case 'weekday':
+    case 'yearday':case 'nlyearday':
+        return [arg, null];
+    default:
+        throw new Error("Unknown relativedelta argument " + arg);
+    }
+});
+args.unshift('*');
+
+var _utils = {
+    monthrange: function (year, month) {
+        if (month < 1 || month > 12) {
+            throw new Error("Illegal month " + month);
+        }
+
+        var day1 = this.weekday(year, month, 1);
+        var ndays = this.mdays[month] + (month == this.February && this.isleap(year));
+        return [day1, ndays];
+    },
+    weekday: function (year, month, day) {
+        var date = py.PY_call(datetime.date, [year, month, day]);
+        return py.PY_call(py.PY_getAttr(date, 'weekday'));
+    },
+    isleap: function (year) {
+        return year % 4 === 0 && (year % 100 !== 0 || year % 400 === 0);
+    },
+    mdays: [0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31],
+    January: 1,
+    February: 2
+};
+
+var relativedelta = py.type('relativedelta', null, {
+    __init__: function () {
+        this.ops = py.PY_parseArgs(arguments, args);
+        this.ops.days = py.float.fromJSON(
+            asJS(this.ops.days) + asJS(this.ops.weeks) * 7
+        );
+
+        var yday = zero;
+        if (this.ops.nlyearday) {
+            yday = this.ops.nlyearday;
+        } else if (this.ops.yearday) {
+            yday = this.ops.yearday;
+            if (asJS(this.ops.yearday) > 59) {
+                this.ops.leapdays = py.float.fromJS(-1);
+            }
+        }
+        if (py.PY_isTrue(yday)) {
+            var ydayidx = [31, 59, 90, 120, 151, 181, 212,
+                           243, 273, 304, 334, 366];
+            for(var idx=0; idx<ydayidx.length; ++idx) {
+                var ydays = ydayidx[idx];
+                if (asJS(yday) <= ydays) {
+                    this.ops.month = py.float.fromJSON(idx+1);
+                    if (!idx) {
+                        this.ops.day = yday;
+                    } else {
+                        this.ops.day = py.PY_subtract(
+                            yday,
+                            py.float.fromJSON(ydayidx[idx-1])
+                        );
+                    }
+                    break;
+                }
+            }
+            if (idx === ydayidx.length) {
+                throw new Error("Invalid year day (" + asJS(yday) + ")");
+            }
+        }
+        this._fix();
+    },
+    _fix: function () {
+        var months = asJS(this.ops.months);
+        if (Math.abs(months) > 11) {
+            var s = months > 0 ? 1 : -1;
+            var r = divmod(months * s, 12);
+            this.ops.months = py.float.fromJSON(r.mod*s);
+            this.ops.years = py.float.fromJSON(
+                asJS(this.ops.years) + r.div*s);
+        }
+        this._has_time = 0;
+    },
+    __add__: function (other) {
+        if (!py.PY_isInstance(other, datetime.date)) {
+            return py.NotImplemented;
+        }
+        // TODO: test this whole mess
+        var year = (asJS(this.ops.year) || asJS(other.year)) + asJS(this.ops.years);
+        var month = asJS(this.ops.month) || asJS(other.month);
+        var months;
+        if (months = asJS(this.ops.months)) {
+            if (Math.abs(months) < 1 || Math.abs(months) > 12) {
+                throw new Error("Can only use relative months between -12 and +12");
+            }
+            month += months;
+            if (month > 12) {
+                year += 1;
+                month -= 12;
+            }
+            if (month < 1) {
+                year -= 1;
+                month += 12;
+            }
+        }
+
+        var day = Math.min(_utils.monthrange(year, month)[1],
+                           asJS(this.ops.day) || asJS(other.day));
+
+        var repl = {
+            year: py.float.fromJSON(year),
+            month: py.float.fromJSON(month),
+            day: py.float.fromJSON(day)
+        };
+
+        var days = asJS(this.ops.days);
+        if (py.PY_isTrue(this.ops.leapdays) && month > 2 && _utils.isleap(year)) {
+            days += asJS(this.ops.leapdays);
+        }
+
+        var ret = py.PY_add(
+            py.PY_call(py.PY_getAttr(other, 'replace'), repl),
+            py.PY_call(datetime.timedelta, {
+                days: py.float.fromJSON(days)
+            })
+        );
+
+        if (this.ops.weekday) {
+            // FIXME: only handles numeric weekdays, not decorated
+            var weekday = asJS(this.ops.weekday), nth = 1;
+            var jumpdays = (Math.abs(nth) - 1) * 7;
+
+            var ret_weekday = asJS(py.PY_call(py.PY_getAttr(ret, 'weekday')));
+            if (nth > 0) {
+                jumpdays += (7-ret_weekday+weekday) % 7;
+            } else {
+                jumpdays += (ret_weekday - weekday) % 7;
+                jumpdays *= -1;
+            }
+            ret = py.PY_add(
+                ret,
+                py.PY_call(datetime.timedelta, {
+                    days: py.float.fromJSON(jumpdays)
+                })
+            );
+        }
+
+        return ret;
+    },
+    __radd__: function (other) {
+        return this.__add__(other);
+    },
+    __rsub__: function (other) {
+        return this.__neg__().__radd__(other);
+    },
+    __neg__: function () {
+        return py.PY_call(relativedelta, {
+            years: py.PY_negative(this.ops.years),
+            months: py.PY_negative(this.ops.months),
+            days: py.PY_negative(this.ops.days),
+            leapdays: this.ops.leapdays,
+            year: this.ops.year,
+            month: this.ops.month,
+            day: this.ops.day,
+            weekday: this.ops.weekday
+        });
+    }
+});
+
+py.extras = {
+    datetime: datetime,
+    time: time,
+    relativedelta: relativedelta,
+};
+
+})(typeof exports === 'undefined' ? py : exports);
diff --git a/addons/web/static/src/js/core/pyeval.js b/addons/web/static/src/js/core/pyeval.js
index ee4ac697fd9..47d6d07bf64 100644
--- a/addons/web/static/src/js/core/pyeval.js
+++ b/addons/web/static/src/js/core/pyeval.js
@@ -2,741 +2,9 @@ odoo.define('web.pyeval', function (require) {
 "use strict";
 
 var core = require('web.core');
-var utils = require('web.utils');
 
 var _t = core._t;
 var py = window.py; // to silence linters
-/*
- * py.js helpers and setup
- */
-
-var obj = function () {};
-obj.prototype = py.object;
-var asJS = function (arg) {
-    if (arg instanceof obj) {
-        return arg.toJSON();
-    }
-    return arg;
-};
-
-var datetime = py.PY_call(py.object);
-
-var zero = py.float.fromJSON(0);
-
-// Port from pypy/lib_pypy/datetime.py
-var DAYS_IN_MONTH = [null, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
-var DAYS_BEFORE_MONTH = [null];
-var dbm = 0;
-
-for (var i=1; i<DAYS_IN_MONTH.length; ++i) {
-    DAYS_BEFORE_MONTH.push(dbm);
-    dbm += DAYS_IN_MONTH[i];
-}
-
-function is_leap(year) {
-    return year % 4 === 0 && (year % 100 !== 0 || year % 400 === 0);
-}
-
-function days_before_year(year) {
-    var y = year - 1;
-    return y*365 + Math.floor(y/4) - Math.floor(y/100) + Math.floor(y/400);
-}
-
-function days_in_month(year, month) {
-    if (month === 2 && is_leap(year)) {
-        return 29;
-    }
-    return DAYS_IN_MONTH[month];
-}
-
-function days_before_month(year, month) {
-    var post_leap_feb = month > 2 && is_leap(year);
-    return DAYS_BEFORE_MONTH[month] + (post_leap_feb ? 1 : 0);
-}
-
-function ymd2ord(year, month, day) {
-    var dim = days_in_month(year, month);
-    if (!(1 <= day && day <= dim)) {
-        throw new Error("ValueError: day must be in 1.." + dim);
-    }
-    return days_before_year(year) +
-           days_before_month(year, month) +
-           day;
-}
-
-var DI400Y = days_before_year(401);
-var DI100Y = days_before_year(101);
-var DI4Y = days_before_year(5);
-
-function ord2ymd(n) {
-    --n;
-    var n400, n100, n4, n1, n0;
-    utils.divmod(n, DI400Y, function (_n400, n) {
-        n400 = _n400;
-        utils.divmod(n, DI100Y, function (_n100, n) {
-            n100 = _n100;
-            utils.divmod(n, DI4Y, function (_n4, n) {
-                n4 = _n4;
-                utils.divmod(n, 365, function (_n1, n) {
-                    n1 = _n1;
-                    n0 = n;
-                });
-            });
-        });
-    });
-
-    n = n0;
-    var year = n400 * 400 + 1 + n100 * 100 + n4 * 4 + n1;
-    if (n1 == 4 || n100 == 100) {
-        utils.assert(n0 === 0);
-        return {
-            year: year - 1,
-            month: 12,
-            day: 31
-        };
-    }
-
-    var leapyear = n1 === 3 && (n4 !== 24 || n100 == 3);
-    utils.assert(leapyear == is_leap(year));
-    var month = (n + 50) >> 5;
-    var preceding = DAYS_BEFORE_MONTH[month] + ((month > 2 && leapyear) ? 1 : 0);
-    if (preceding > n) {
-        --month;
-        preceding -= DAYS_IN_MONTH[month] + ((month === 2 && leapyear) ? 1 : 0);
-    }
-    n -= preceding;
-    return {
-        year: year,
-        month: month,
-        day: n+1
-    };
-}
-
-/**
- * Converts the stuff passed in into a valid date, applying overflows as needed
- */
-function tmxxx(year, month, day, hour, minute, second, microsecond) {
-    hour = hour || 0; minute = minute || 0; second = second || 0;
-    microsecond = microsecond || 0;
-
-    if (microsecond < 0 || microsecond > 999999) {
-        utils.divmod(microsecond, 1000000, function (carry, ms) {
-            microsecond = ms;
-            second += carry;
-        });
-    }
-    if (second < 0 || second > 59) {
-        utils.divmod(second, 60, function (carry, s) {
-            second = s;
-            minute += carry;
-        });
-    }
-    if (minute < 0 || minute > 59) {
-        utils.divmod(minute, 60, function (carry, m) {
-            minute = m;
-            hour += carry;
-        });
-    }
-    if (hour < 0 || hour > 23) {
-        utils.divmod(hour, 24, function (carry, h) {
-            hour = h;
-            day += carry;
-        });
-    }
-    // That was easy.  Now it gets muddy:  the proper range for day
-    // can't be determined without knowing the correct month and year,
-    // but if day is, e.g., plus or minus a million, the current month
-    // and year values make no sense (and may also be out of bounds
-    // themselves).
-    // Saying 12 months == 1 year should be non-controversial.
-    if (month < 1 || month > 12) {
-        utils.divmod(month-1, 12, function (carry, m) {
-            month = m + 1;
-            year += carry;
-        });
-    }
-    // Now only day can be out of bounds (year may also be out of bounds
-    // for a datetime object, but we don't care about that here).
-    // If day is out of bounds, what to do is arguable, but at least the
-    // method here is principled and explainable.
-    var dim = days_in_month(year, month);
-    if (day < 1 || day > dim) {
-        // Move day-1 days from the first of the month.  First try to
-        // get off cheap if we're only one day out of range (adjustments
-        // for timezone alone can't be worse than that).
-        if (day === 0) {
-            --month;
-            if (month > 0) {
-                day = days_in_month(year, month);
-            } else {
-                --year; month=12; day=31;
-            }
-        } else if (day == dim + 1) {
-            ++month;
-            day = 1;
-            if (month > 12) {
-                month = 1;
-                ++year;
-            }
-        } else {
-            var r = ord2ymd(ymd2ord(year, month, 1) + (day - 1));
-            year = r.year;
-            month = r.month;
-            day = r.day;
-        }
-    }
-    return {
-        year: year,
-        month: month,
-        day: day,
-        hour: hour,
-        minute: minute,
-        second: second,
-        microsecond: microsecond
-    };
-}
-
-datetime.timedelta = py.type('timedelta', null, {
-    __init__: function () {
-        var args = py.PY_parseArgs(arguments, [
-            ['days', zero], ['seconds', zero], ['microseconds', zero],
-            ['milliseconds', zero], ['minutes', zero], ['hours', zero],
-            ['weeks', zero]
-        ]);
-
-        var d = 0, s = 0, m = 0;
-        var days = args.days.toJSON() + args.weeks.toJSON() * 7;
-        var seconds = args.seconds.toJSON()
-                    + args.minutes.toJSON() * 60
-                    + args.hours.toJSON() * 3600;
-        var microseconds = args.microseconds.toJSON()
-                         + args.milliseconds.toJSON() * 1000;
-
-        // Get rid of all fractions, and normalize s and us.
-        // Take a deep breath <wink>.
-        var daysecondsfrac = utils.modf(days, function (dayfrac, days) {
-            d = days;
-            if (dayfrac) {
-                return utils.modf(dayfrac * 24 * 3600, function (dsf, dsw) {
-                    s = dsw;
-                    return dsf;
-                });
-            }
-            return 0;
-        });
-
-        var secondsfrac = utils.modf(seconds, function (sf, s) {
-            seconds = s;
-            return sf + daysecondsfrac;
-        });
-        utils.divmod(seconds, 24*3600, function (days, seconds) {
-            d += days;
-            s += seconds;
-        });
-        // seconds isn't referenced again before redefinition
-
-        microseconds += secondsfrac * 1e6;
-        utils.divmod(microseconds, 1000000, function (seconds, microseconds) {
-            utils.divmod(seconds, 24*3600, function (days, seconds) {
-                d += days;
-                s += seconds;
-                m += Math.round(microseconds);
-            });
-        });
-
-        // Carrying still possible here?
-
-        this.days = d;
-        this.seconds = s;
-        this.microseconds = m;
-    },
-    __str__: function () {
-        var hh, mm, ss;
-        utils.divmod(this.seconds, 60, function (m, s) {
-            utils.divmod(m, 60, function (h, m) {
-                hh = h;
-                mm = m;
-                ss = s;
-            });
-        });
-        var s = _.str.sprintf("%d:%02d:%02d", hh, mm, ss);
-        if (this.days) {
-            s = _.str.sprintf("%d day%s, %s",
-                this.days,
-                (this.days != 1 && this.days != -1) ? 's' : '',
-                s);
-        }
-        if (this.microseconds) {
-            s = _.str.sprintf("%s.%06d", s, this.microseconds);
-        }
-        return py.str.fromJSON(s);
-    },
-    __eq__: function (other) {
-        if (!py.PY_isInstance(other, datetime.timedelta)) {
-            return py.False;
-        }
-
-        return (this.days === other.days
-            && this.seconds === other.seconds
-            && this.microseconds === other.microseconds)
-                ? py.True : py.False;
-    },
-    __add__: function (other) {
-        if (!py.PY_isInstance(other, datetime.timedelta)) {
-            return py.NotImplemented;
-        }
-        return py.PY_call(datetime.timedelta, [
-            py.float.fromJSON(this.days + other.days),
-            py.float.fromJSON(this.seconds + other.seconds),
-            py.float.fromJSON(this.microseconds + other.microseconds)
-        ]);
-    },
-    __radd__: function (other) { return this.__add__(other); },
-    __sub__: function (other) {
-        if (!py.PY_isInstance(other, datetime.timedelta)) {
-            return py.NotImplemented;
-        }
-        return py.PY_call(datetime.timedelta, [
-            py.float.fromJSON(this.days - other.days),
-            py.float.fromJSON(this.seconds - other.seconds),
-            py.float.fromJSON(this.microseconds - other.microseconds)
-        ]);
-    },
-    __rsub__: function (other) {
-        if (!py.PY_isInstance(other, datetime.timedelta)) {
-            return py.NotImplemented;
-        }
-        return this.__neg__().__add__(other);
-    },
-    __neg__: function () {
-        return py.PY_call(datetime.timedelta, [
-            py.float.fromJSON(-this.days),
-            py.float.fromJSON(-this.seconds),
-            py.float.fromJSON(-this.microseconds)
-        ]);
-    },
-    __pos__: function () { return this; },
-    __mul__: function (other) {
-        if (!py.PY_isInstance(other, py.float)) {
-            return py.NotImplemented;
-        }
-        var n = other.toJSON();
-        return py.PY_call(datetime.timedelta, [
-            py.float.fromJSON(this.days * n),
-            py.float.fromJSON(this.seconds * n),
-            py.float.fromJSON(this.microseconds * n)
-        ]);
-    },
-    __rmul__: function (other) { return this.__mul__(other); },
-    __div__: function (other) {
-        if (!py.PY_isInstance(other, py.float)) {
-            return py.NotImplemented;
-        }
-        var usec = ((this.days * 24 * 3600) + this.seconds) * 1000000
-                    + this.microseconds;
-        return py.PY_call(
-            datetime.timedelta, [
-                zero, zero, py.float.fromJSON(usec / other.toJSON())]);
-    },
-    __floordiv__: function (other) { return this.__div__(other); },
-    total_seconds: function () {
-        return py.float.fromJSON(
-            this.days * 86400
-          + this.seconds
-          + this.microseconds / 1000000);
-    },
-    __nonzero__: function () {
-        return (!!this.days || !!this.seconds || !!this.microseconds)
-            ? py.True
-            : py.False;
-    }
-});
-
-datetime.datetime = py.type('datetime', null, {
-    __init__: function () {
-        var zero = py.float.fromJSON(0);
-        var args = py.PY_parseArgs(arguments, [
-            'year', 'month', 'day',
-            ['hour', zero], ['minute', zero], ['second', zero],
-            ['microsecond', zero], ['tzinfo', py.None]
-        ]);
-        for(var key in args) {
-            if (!args.hasOwnProperty(key)) { continue; }
-            this[key] = asJS(args[key]);
-        }
-    },
-    replace: function () {
-        var args = py.PY_parseArgs(arguments, [
-            ['year', py.None], ['month', py.None], ['day', py.None],
-            ['hour', py.None], ['minute', py.None], ['second', py.None],
-            ['microsecond', py.None] // FIXME: tzinfo, can't use None as valid input
-        ]);
-        var params = {};
-        for(var key in args) {
-            if (!args.hasOwnProperty(key)) { continue; }
-
-            var arg = args[key];
-            params[key] = (arg === py.None ? this[key] : asJS(arg));
-        }
-        return py.PY_call(datetime.datetime, params);
-    },
-    strftime: function () {
-        var self = this;
-        var args = py.PY_parseArgs(arguments, 'format');
-        return py.str.fromJSON(args.format.toJSON()
-            .replace(/%([A-Za-z])/g, function (m, c) {
-                switch (c) {
-                case 'Y': return _.str.sprintf('%04d', self.year);
-                case 'm': return _.str.sprintf('%02d', self.month);
-                case 'd': return _.str.sprintf('%02d', self.day);
-                case 'H': return _.str.sprintf('%02d', self.hour);
-                case 'M': return _.str.sprintf('%02d', self.minute);
-                case 'S': return _.str.sprintf('%02d', self.second);
-                }
-                throw new Error('ValueError: No known conversion for ' + m);
-            }));
-    },
-    now: py.classmethod.fromJSON(function () {
-        var d = new Date();
-        return py.PY_call(datetime.datetime, [
-            d.getFullYear(), d.getMonth() + 1, d.getDate(),
-            d.getHours(), d.getMinutes(), d.getSeconds(),
-            d.getMilliseconds() * 1000]);
-    }),
-    today: py.classmethod.fromJSON(function () {
-        var dt_class = py.PY_getAttr(datetime, 'datetime');
-        return py.PY_call(py.PY_getAttr(dt_class, 'now'));
-    }),
-    utcnow: py.classmethod.fromJSON(function () {
-        var d = new Date();
-        return py.PY_call(datetime.datetime,
-            [d.getUTCFullYear(), d.getUTCMonth() + 1, d.getUTCDate(),
-             d.getUTCHours(), d.getUTCMinutes(), d.getUTCSeconds(),
-             d.getUTCMilliseconds() * 1000]);
-    }),
-    combine: py.classmethod.fromJSON(function () {
-        var args = py.PY_parseArgs(arguments, 'date time');
-        return py.PY_call(datetime.datetime, [
-            py.PY_getAttr(args.date, 'year'),
-            py.PY_getAttr(args.date, 'month'),
-            py.PY_getAttr(args.date, 'day'),
-            py.PY_getAttr(args.time, 'hour'),
-            py.PY_getAttr(args.time, 'minute'),
-            py.PY_getAttr(args.time, 'second')
-        ]);
-    }),
-    toJSON: function () {
-        return new Date(
-            this.year,
-            this.month - 1,
-            this.day,
-            this.hour,
-            this.minute,
-            this.second,
-            this.microsecond / 1000);
-    },
-    __add__: function (other) {
-        if (!py.PY_isInstance(other, datetime.timedelta)) {
-            return py.NotImplemented;
-        }
-        var s = tmxxx(this.year, this.month, this.day + other.days, this.hour, this.minute, this.second + other.seconds);
-        return datetime.datetime.fromJSON(s.year, s.month, s.day, s.hour, s.minute, s.second);
-    },
-    __sub__: function (other) {
-        if (py.PY_isInstance(other, datetime.timedelta)) {
-            return py.PY_add(this, py.PY_negative(other));
-        }
-        return py.NotImplemented;
-    },
-    fromJSON: function (year, month, day, hour, minute, second) {
-        return py.PY_call(datetime.datetime, [year, month, day, hour, minute, second]);
-    },
-});
-
-datetime.date = py.type('date', null, {
-    __init__: function () {
-        var args = py.PY_parseArgs(arguments, 'year month day');
-        this.year = asJS(args.year);
-        this.month = asJS(args.month);
-        this.day = asJS(args.day);
-    },
-    strftime: function () {
-        var self = this;
-        var args = py.PY_parseArgs(arguments, 'format');
-        return py.str.fromJSON(args.format.toJSON()
-            .replace(/%([A-Za-z])/g, function (m, c) {
-                switch (c) {
-                case 'Y': return self.year;
-                case 'm': return _.str.sprintf('%02d', self.month);
-                case 'd': return _.str.sprintf('%02d', self.day);
-                }
-                throw new Error('ValueError: No known conversion for ' + m);
-            }));
-    },
-    __eq__: function (other) {
-        return (this.year === other.year
-             && this.month === other.month
-             && this.day === other.day)
-            ? py.True : py.False;
-    },
-    replace: function () {
-        var args = py.PY_parseArgs(arguments, [
-            ['year', py.None], ['month', py.None], ['day', py.None]
-        ]);
-        var params = {};
-        for(var key in args) {
-            if (!args.hasOwnProperty(key)) { continue; }
-
-            var arg = args[key];
-            params[key] = (arg === py.None ? this[key] : asJS(arg));
-        }
-        return py.PY_call(datetime.date, params);
-    },
-    __add__: function (other) {
-        if (!py.PY_isInstance(other, datetime.timedelta)) {
-            return py.NotImplemented;
-        }
-        var s = tmxxx(this.year, this.month, this.day + other.days);
-        return datetime.date.fromJSON(s.year, s.month, s.day);
-    },
-    __radd__: function (other) { return this.__add__(other); },
-    __sub__: function (other) {
-        if (py.PY_isInstance(other, datetime.timedelta)) {
-            return py.PY_add(this, py.PY_negative(other));
-        }
-        if (py.PY_isInstance(other, datetime.date)) {
-            // FIXME: getattr and sub API methods
-            return py.PY_call(datetime.timedelta, [
-                py.PY_subtract(
-                    py.PY_call(py.PY_getAttr(this, 'toordinal')),
-                    py.PY_call(py.PY_getAttr(other, 'toordinal')))
-            ]);
-        }
-        return py.NotImplemented;
-    },
-    toordinal: function () {
-        return py.float.fromJSON(ymd2ord(this.year, this.month, this.day));
-    },
-    weekday: function () {
-        return  py.float.fromJSON((this.toordinal().toJSON()+6)%7);
-    },
-    fromJSON: function (year, month, day) {
-        return py.PY_call(datetime.date, [year, month, day]);
-    },
-    today: py.classmethod.fromJSON(function () {
-        var d = new Date ();
-        return py.PY_call(datetime.date, [
-            d.getFullYear(), d.getMonth() + 1, d.getDate()]);
-    }),
-});
-/**
- * Returns the current local date, which means the date on the client (which can be different
- * compared to the date of the server).
- *
- * @return {datetime.date}
- */
-function context_today() {
-    var d = new Date();
-    return py.PY_call(
-        datetime.date, [d.getFullYear(), d.getMonth() + 1, d.getDate()]);
-}
-
-datetime.time = py.type('time', null, {
-    __init__: function () {
-        var zero = py.float.fromJSON(0);
-        var args = py.PY_parseArgs(arguments, [
-            ['hour', zero], ['minute', zero], ['second', zero], ['microsecond', zero],
-            ['tzinfo', py.None]
-        ]);
-
-        for(var k in args) {
-            if (!args.hasOwnProperty(k)) { continue; }
-            this[k] = asJS(args[k]);
-        }
-    }
-});
-
-var time = py.PY_call(py.object);
-time.strftime = py.PY_def.fromJSON(function () {
-    var args  = py.PY_parseArgs(arguments, 'format');
-    var dt_class = py.PY_getAttr(datetime, 'datetime');
-    var d = py.PY_call(py.PY_getAttr(dt_class, 'utcnow'));
-    return py.PY_call(py.PY_getAttr(d, 'strftime'), [args.format]);
-});
-
-var args = _.map(('year month day '
-                + 'years months weeks days '
-                + 'weekday leapdays yearday nlyearday').split(' '), function (arg) {
-    switch (arg) {
-    case 'years':case 'months':case 'days':case 'leapdays':case 'weeks':
-        return [arg, zero];
-    case 'year':case 'month':case 'day':case 'weekday':
-    case 'yearday':case 'nlyearday':
-        return [arg, null];
-    default:
-        throw new Error("Unknown relativedelta argument " + arg);
-    }
-});
-args.unshift('*');
-
-var _utils = {
-    monthrange: function (year, month) {
-        if (month < 1 || month > 12) {
-            throw new Error("Illegal month " + month);
-        }
-
-        var day1 = this.weekday(year, month, 1);
-        var ndays = this.mdays[month] + (month == this.February && this.isleap(year));
-        return [day1, ndays];
-    },
-    weekday: function (year, month, day) {
-        var date = py.PY_call(datetime.date, [year, month, day]);
-        return py.PY_call(py.PY_getAttr(date, 'weekday'));
-    },
-    isleap: function (year) {
-        return year % 4 === 0 && (year % 100 !== 0 || year % 400 === 0);
-    },
-    mdays: [0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31],
-    January: 1,
-    February: 2
-};
-
-var relativedelta = py.type('relativedelta', null, {
-    __init__: function () {
-        this.ops = py.PY_parseArgs(arguments, args);
-        this.ops.days = py.float.fromJSON(
-            asJS(this.ops.days) + asJS(this.ops.weeks) * 7
-        );
-
-        var yday = zero;
-        if (this.ops.nlyearday) {
-            yday = this.ops.nlyearday;
-        } else if (this.ops.yearday) {
-            yday = this.ops.yearday;
-            if (asJS(this.ops.yearday) > 59) {
-                this.ops.leapdays = py.float.fromJS(-1);
-            }
-        }
-        if (py.PY_isTrue(yday)) {
-            var ydayidx = [31, 59, 90, 120, 151, 181, 212,
-                           243, 273, 304, 334, 366];
-            for(var idx=0; idx<ydayidx.length; ++idx) {
-                var ydays = ydayidx[idx];
-                if (asJS(yday) <= ydays) {
-                    this.ops.month = py.float.fromJSON(idx+1);
-                    if (!idx) {
-                        this.ops.day = yday;
-                    } else {
-                        this.ops.day = py.PY_subtract(
-                            yday,
-                            py.float.fromJSON(ydayidx[idx-1])
-                        );
-                    }
-                    break;
-                }
-            }
-            if (idx === ydayidx.length) {
-                throw new Error("Invalid year day (" + asJS(yday) + ")");
-            }
-        }
-        this._fix();
-    },
-    _fix: function () {
-        var months = asJS(this.ops.months);
-        if (Math.abs(months) > 11) {
-            var s = months > 0 ? 1 : -1;
-            var r = utils.divmod(months * s, 12);
-            this.ops.months = py.float.fromJSON(r.mod*s);
-            this.ops.years = py.float.fromJSON(
-                asJS(this.ops.years) + r.div*s);
-        }
-        this._has_time = 0;
-    },
-    __add__: function (other) {
-        if (!py.PY_isInstance(other, datetime.date)) {
-            return py.NotImplemented;
-        }
-        // TODO: test this whole mess
-        var year = (asJS(this.ops.year) || asJS(other.year)) + asJS(this.ops.years);
-        var month = asJS(this.ops.month) || asJS(other.month);
-        var months;
-        if (months = asJS(this.ops.months)) {
-            if (Math.abs(months) < 1 || Math.abs(months) > 12) {
-                throw new Error("Can only use relative months between -12 and +12");
-            }
-            month += months;
-            if (month > 12) {
-                year += 1;
-                month -= 12;
-            }
-            if (month < 1) {
-                year -= 1;
-                month += 12;
-            }
-        }
-
-        var day = Math.min(_utils.monthrange(year, month)[1],
-                           asJS(this.ops.day) || asJS(other.day));
-
-        var repl = {
-            year: py.float.fromJSON(year),
-            month: py.float.fromJSON(month),
-            day: py.float.fromJSON(day)
-        };
-
-        var days = asJS(this.ops.days);
-        if (py.PY_isTrue(this.ops.leapdays) && month > 2 && _utils.isleap(year)) {
-            days += asJS(this.ops.leapdays);
-        }
-
-        var ret = py.PY_add(
-            py.PY_call(py.PY_getAttr(other, 'replace'), repl),
-            py.PY_call(datetime.timedelta, {
-                days: py.float.fromJSON(days)
-            })
-        );
-
-        if (this.ops.weekday) {
-            // FIXME: only handles numeric weekdays, not decorated
-            var weekday = asJS(this.ops.weekday), nth = 1;
-            var jumpdays = (Math.abs(nth) - 1) * 7;
-
-            var ret_weekday = asJS(py.PY_call(py.PY_getAttr(ret, 'weekday')));
-            if (nth > 0) {
-                jumpdays += (7-ret_weekday+weekday) % 7;
-            } else {
-                jumpdays += (ret_weekday - weekday) % 7;
-                jumpdays *= -1;
-            }
-            ret = py.PY_add(
-                ret,
-                py.PY_call(datetime.timedelta, {
-                    days: py.float.fromJSON(jumpdays)
-                })
-            );
-        }
-
-        return ret;
-    },
-    __radd__: function (other) {
-        return this.__add__(other);
-    },
-    __rsub__: function (other) {
-        return this.__neg__().__radd__(other);
-    },
-    __neg__: function () {
-        return py.PY_call(relativedelta, {
-            years: py.PY_negative(this.ops.years),
-            months: py.PY_negative(this.ops.months),
-            days: py.PY_negative(this.ops.days),
-            leapdays: this.ops.leapdays,
-            year: this.ops.year,
-            month: this.ops.month,
-            day: this.ops.day,
-            weekday: this.ops.weekday
-        });
-    }
-});
 
 // recursively wraps JS objects passed into the context to attributedicts
 // which jsonify back to JS objects
@@ -951,15 +219,27 @@ function eval_groupbys(contexts, evaluation_context) {
     return result_group;
 }
 
+/**
+ * Returns the current local date, which means the date on the client (which can be different
+ * compared to the date of the server).
+ *
+ * @return {datetime.date}
+ */
+function context_today() {
+    var d = new Date();
+    return py.PY_call(
+        py.extras.datetime.date, [d.getFullYear(), d.getMonth() + 1, d.getDate()]);
+}
+
 
 function pycontext() {
     return {
-        datetime: datetime,
+        datetime: py.extras.datetime,
         context_today: context_today,
-        time: time,
-        relativedelta: relativedelta,
+        time: py.extras.time,
+        relativedelta: py.extras.relativedelta,
         current_date: py.PY_call(
-            time.strftime, [py.str.fromJSON('%Y-%m-%d')]),
+            py.extras.time.strftime, [py.str.fromJSON('%Y-%m-%d')]),
     };
 }
 
diff --git a/addons/web/static/src/js/core/utils.js b/addons/web/static/src/js/core/utils.js
index ffeb4a1de87..3068a6528c9 100644
--- a/addons/web/static/src/js/core/utils.js
+++ b/addons/web/static/src/js/core/utils.js
@@ -52,20 +52,6 @@ var utils = {
         return Math.max(min, Math.min(max, val));
     },
     /**
-     * computes (Math.floor(a/b), a%b and passes that to the callback.
-     *
-     * returns the callback's result
-     */
-    divmod: function (a, b, fn) {
-        var mod = a%b;
-        // in python, sign(a % b) === sign(b). Not in JS. If wrong side, add a
-        // round of b
-        if (mod > 0 && b < 0 || mod < 0 && b > 0) {
-            mod += b;
-        }
-        return fn(Math.floor(a/b), mod);
-    },
-    /**
      * @param {number} value
      * @param {integer} decimals
      * @returns {boolean}
@@ -290,17 +276,6 @@ var utils = {
         return new Array(size - str.length + 1).join('0') + str;
     },
     /**
-     * Passes the fractional and integer parts of x to the callback, returns
-     * the callback's result
-     */
-    modf: function (x, fn) {
-        var mod = x%1;
-        if (mod < 0) {
-            mod += 1;
-        }
-        return fn(mod, Math.floor(x));
-    },
-    /**
      * performs a half up rounding with a fixed amount of decimals, correcting for float loss of precision
      * See the corresponding float_round() in server/tools/float_utils.py for more info
      * @param {Number} value the value to be rounded
diff --git a/addons/web/views/webclient_templates.xml b/addons/web/views/webclient_templates.xml
index e4c28872b64..ed40fb36625 100644
--- a/addons/web/views/webclient_templates.xml
+++ b/addons/web/views/webclient_templates.xml
@@ -173,6 +173,7 @@
         </script>
 
         <script type="text/javascript" src="/web/static/lib/py.js/lib/py.js"></script>
+        <script type="text/javascript" src="/web/static/lib/py.js/lib/py_extras.js"></script>
         <!-- Special case: core.js declares $.browser needed by ba-bbq -->
         <script type="text/javascript" src="/web/static/lib/jquery.ba-bbq/jquery.ba-bbq.js"></script>