[REF] web, *: redesign all JS views

This commit introduce a full redesign of all JS views.  We started
basically from scratch.  The goal was to unify all the various views
under a common framework, to make them testable, to make then usable in
different conditions (in studio, or in the frontend), and to make our
lives easier.

Some important points are:
- we introduced new coding guidelines (camelCase, 80 chars width, ...)
- we have a brand new testing framework (still QUnit based)
- kanban view moved to the web addon
- calendar view (formerly web_calender) moved to web as well
- the tree view was removed
- all new code should be documented

We hope that this code is the start of a new era for the Odoo web
client, we want to have a high quality codebase, well documented, well
tested, well designed.

Work done by the framework team: mostly aab, ged, chm, dmo, qsm

1 files changed, 1036 insertions, 0 deletions

diff --git a/addons/web/static/src/js/core/pyeval.js b/addons/web/static/src/js/core/pyeval.js
new file mode 100644
index 00000000000..df56f60074a
--- /dev/null
+++ b/addons/web/static/src/js/core/pyeval.js
@@ -0,0 +1,1036 @@
+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);
+    },
+});
+
+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
+function wrap(value) {
+    if (value === null) { return py.None; }
+
+    switch (typeof value) {
+    case 'undefined': throw new Error("No conversion for undefined");
+    case 'boolean': return py.bool.fromJSON(value);
+    case 'number': return py.float.fromJSON(value);
+    case 'string': return py.str.fromJSON(value);
+    }
+
+    switch(value.constructor) {
+    case Object: return wrapping_dict.fromJSON(value);
+    case Array: return wrapping_list.fromJSON(value);
+    }
+
+    throw new Error("ValueError: unable to wrap " + value);
+}
+
+var wrapping_dict = py.type('wrapping_dict', null, {
+    __init__: function () {
+        this._store = {};
+    },
+    __getitem__: function (key) {
+        var k = key.toJSON();
+        if (!(k in this._store)) {
+            throw new Error("KeyError: '" + k + "'");
+        }
+        return wrap(this._store[k]);
+    },
+    __getattr__: function (key) {
+        return this.__getitem__(py.str.fromJSON(key));
+    },
+    __len__: function () {
+        return Object.keys(this._store).length
+    },
+    __nonzero__: function () {
+        return py.PY_size(this) > 0 ? py.True : py.False;
+    },
+    get: function () {
+        var args = py.PY_parseArgs(arguments, ['k', ['d', py.None]]);
+
+        if (!(args.k.toJSON() in this._store)) { return args.d; }
+        return this.__getitem__(args.k);
+    },
+    fromJSON: function (d) {
+        var instance = py.PY_call(wrapping_dict);
+        instance._store = d;
+        return instance;
+    },
+    toJSON: function () {
+        return this._store;
+    },
+});
+
+var wrapping_list = py.type('wrapping_list', null, {
+    __init__: function () {
+        this._store = [];
+    },
+    __getitem__: function (index) {
+        return wrap(this._store[index.toJSON()]);
+    },
+    __len__: function () {
+        return this._store.length;
+    },
+    __nonzero__: function () {
+        return py.PY_size(this) > 0 ? py.True : py.False;
+    },
+    fromJSON: function (ar) {
+        var instance = py.PY_call(wrapping_list);
+        instance._store = ar;
+        return instance;
+    },
+    toJSON: function () {
+        return this._store;
+    },
+});
+
+function wrap_context (context) {
+    for (var k in context) {
+        if (!context.hasOwnProperty(k)) { continue; }
+        var val = context[k];
+
+        if (val === null) { continue; }
+        if (val.constructor === Array) {
+            context[k] = wrapping_list.fromJSON(val);
+        } else if (val.constructor === Object
+                   && !py.PY_isInstance(val, py.object)) {
+            context[k] = wrapping_dict.fromJSON(val);
+        }
+    }
+    return context;
+}
+
+function eval_contexts (contexts, evaluation_context) {
+    evaluation_context = _.extend(pycontext(), evaluation_context || {});
+    return _(contexts).reduce(function (result_context, ctx) {
+        // __eval_context evaluations can lead to some of `contexts`'s
+        // values being null, skip them as well as empty contexts
+        if (_.isEmpty(ctx)) { return result_context; }
+        if (_.isString(ctx)) {
+            // wrap raw strings in context
+            ctx = { __ref: 'context', __debug: ctx };
+        }
+        var evaluated = ctx;
+        switch(ctx.__ref) {
+        case 'context':
+            evaluation_context.context = evaluation_context;
+            evaluated = py.eval(ctx.__debug, wrap_context(evaluation_context));
+            break;
+        case 'compound_context':
+            var eval_context = eval_contexts([ctx.__eval_context]);
+            evaluated = eval_contexts(
+                ctx.__contexts, _.extend({}, evaluation_context, eval_context));
+            break;
+        }
+        // add newly evaluated context to evaluation context for following
+        // siblings
+        _.extend(evaluation_context, evaluated);
+        return _.extend(result_context, evaluated);
+    }, {});
+}
+
+function eval_domains (domains, evaluation_context) {
+    evaluation_context = _.extend(pycontext(), evaluation_context || {});
+    var result_domain = [];
+    // Normalize only if the first domain is the array ["|"] or ["!"]
+    var need_normalization = (
+        domains &&
+        domains.length > 0 &&
+        domains[0].length === 1 &&
+        (domains[0][0] === "|" || domains[0][0] === "!")
+    );
+    _(domains).each(function (domain) {
+        if (_.isString(domain)) {
+            // wrap raw strings in domain
+            domain = { __ref: 'domain', __debug: domain };
+        }
+        var domain_array_to_combine;
+        switch(domain.__ref) {
+        case 'domain':
+            evaluation_context.context = evaluation_context;
+            domain_array_to_combine = py.eval(domain.__debug, wrap_context(evaluation_context));
+            break;
+        case 'compound_domain':
+            var eval_context = eval_contexts([domain.__eval_context]);
+            domain_array_to_combine = eval_domains(
+                domain.__domains, _.extend({}, evaluation_context, eval_context)
+            );
+            break;
+        default:
+            domain_array_to_combine = domain;
+        }
+        if (need_normalization) {
+            domain_array_to_combine = get_normalized_domain(domain_array_to_combine);
+        }
+        result_domain.push.apply(result_domain, domain_array_to_combine);
+    });
+    return result_domain;
+}
+
+/**
+ * Returns a normalized copy of the given domain array. Normalization is
+ * is making the implicit "&" at the start of the domain explicit, e.g.
+ * [A, B, C] would become ["&", "&", A, B, C].
+ *
+ * @param {Array} domain_array
+ * @returns {Array} normalized copy of the given array
+ */
+function get_normalized_domain(domain_array) {
+    var expected = 1; // Holds the number of expected domain expressions
+    _.each(domain_array, function (item) {
+        if (item === "&" || item === "|") {
+            expected++;
+        } else if (item !== "!") {
+            expected--;
+        }
+    });
+    var new_explicit_ands = _.times(-expected, _.constant("&"));
+    return new_explicit_ands.concat(domain_array);
+}
+
+function eval_groupbys (contexts, evaluation_context) {
+    evaluation_context = _.extend(pycontext(), evaluation_context || {});
+    var result_group = [];
+    _(contexts).each(function (ctx) {
+        if (_.isString(ctx)) {
+            // wrap raw strings in context
+            ctx = { __ref: 'context', __debug: ctx };
+        }
+        var group;
+        var evaluated = ctx;
+        switch(ctx.__ref) {
+        case 'context':
+            evaluation_context.context = evaluation_context;
+            evaluated = py.eval(ctx.__debug, wrap_context(evaluation_context));
+            break;
+        case 'compound_context':
+            var eval_context = eval_contexts([ctx.__eval_context]);
+            evaluated = eval_contexts(
+                ctx.__contexts, _.extend({}, evaluation_context, eval_context));
+            break;
+        }
+        group = evaluated.group_by;
+        if (!group) { return; }
+        if (typeof group === 'string') {
+            result_group.push(group);
+        } else if (group instanceof Array) {
+            result_group.push.apply(result_group, group);
+        } else {
+            throw new Error('Got invalid groupby {{'
+                    + JSON.stringify(group) + '}}');
+        }
+        _.extend(evaluation_context, evaluated);
+    });
+    return result_group;
+}
+
+
+function pycontext () {
+    return {
+        datetime: datetime,
+        context_today: context_today,
+        time: time,
+        relativedelta: relativedelta,
+        current_date: py.PY_call(
+            time.strftime, [py.str.fromJSON('%Y-%m-%d')]),
+    };
+}
+
+/**
+ * @param {String} type "domains", "contexts" or "groupbys"
+ * @param {Array} object domains or contexts to evaluate
+ * @param {Object} [context] evaluation context
+ */
+function pyeval (type, object, context) {
+    context = _.extend(pycontext(), context || {});
+
+    //noinspection FallthroughInSwitchStatementJS
+    switch(type) {
+    case 'context':
+    case 'contexts':
+        if (type === 'context') {
+            object = [object];
+        }
+        return eval_contexts(object, context);
+    case 'domain':
+    case 'domains':
+        if (type === 'domain')
+            object = [object];
+        return eval_domains(object, context);
+    case 'groupbys':
+        return eval_groupbys(object, context);
+    }
+    throw new Error("Unknow evaluation type " + type);
+}
+
+function eval_arg (arg) {
+    if (typeof arg !== 'object' || !arg.__ref) { return arg; }
+    switch(arg.__ref) {
+    case 'domain': case 'compound_domain':
+        return pyeval('domains', [arg]);
+    case 'context': case 'compound_context':
+        return pyeval('contexts', [arg]);
+    default:
+        throw new Error(_t("Unknown nonliteral type ") + ' ' + arg.__ref);
+    }
+}
+
+/**
+ * If args or kwargs are unevaluated contexts or domains (compound or not),
+ * evaluated them in-place.
+ *
+ * Potentially mutates both parameters.
+ *
+ * @param args
+ * @param kwargs
+ */
+function ensure_evaluated (args, kwargs) {
+    for (var i=0; i<args.length; ++i) {
+        args[i] = eval_arg(args[i]);
+    }
+    for (var k in kwargs) {
+        if (!kwargs.hasOwnProperty(k)) { continue; }
+        kwargs[k] = eval_arg(kwargs[k]);
+    }
+}
+
+function eval_domains_and_contexts (source) {
+    // see Session.eval_context in Python
+    return {
+        context: pyeval('contexts', source.contexts || [], source.eval_context),
+        domain: pyeval('domains', source.domains, source.eval_context),
+        group_by: pyeval('groupbys', source.group_by_seq || [], source.eval_context),
+    };
+}
+
+function py_eval (expr, context) {
+    return py.eval(expr, _.extend({}, context || {}, {"true": true, "false": false, "null": null}));
+}
+
+
+return {
+    context: pycontext,
+    ensure_evaluated: ensure_evaluated,
+    eval: pyeval,
+    eval_domains_and_contexts: eval_domains_and_contexts,
+    py_eval: py_eval,
+};
+
+});