/
math.dart
304 lines (257 loc) · 9.58 KB
/
math.dart
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
// Copyright 2019 Google Inc. Use of this source code is governed by an
// MIT-style license that can be found in the LICENSE file or at
// https://opensource.org/licenses/MIT.
import 'dart:collection';
import 'dart:math' as math;
import 'package:collection/collection.dart';
import '../callable.dart';
import '../evaluation_context.dart';
import '../exception.dart';
import '../module/built_in.dart';
import '../value.dart';
/// The global definitions of Sass math functions.
final global = UnmodifiableListView([
_abs, _ceil, _floor, _max, _min, _percentage, _randomFunction, _round,
_unit, //
_compatible.withName("comparable"),
_isUnitless.withName("unitless"),
]);
/// The Sass math module.
final module = BuiltInModule("math", functions: [
_abs, _acos, _asin, _atan, _atan2, _ceil, _clamp, _cos, _compatible, //
_floor, _hypot, _isUnitless, _log, _max, _min, _percentage, _pow, //
_randomFunction, _round, _sin, _sqrt, _tan, _unit, _div
], variables: {
"e": SassNumber(math.e),
"pi": SassNumber(math.pi),
"epsilon": SassNumber(2.220446049250313e-16),
"max-safe-integer": SassNumber(9007199254740991),
"min-safe-integer": SassNumber(-9007199254740991),
"max-number": SassNumber(double.maxFinite),
"min-number": SassNumber(double.minPositive),
});
///
/// Bounding functions
///
final _ceil = _numberFunction("ceil", (value) => value.ceil().toDouble());
final _clamp = _function("clamp", r"$min, $number, $max", (arguments) {
var min = arguments[0].assertNumber("min");
var number = arguments[1].assertNumber("number");
var max = arguments[2].assertNumber("max");
// Even though we don't use the resulting values, `convertValueToMatch`
// generates more user-friendly exceptions than [greaterThanOrEquals] since it
// has more context about parameter names.
number.convertValueToMatch(min, "number", "min");
max.convertValueToMatch(min, "max", "min");
if (min.greaterThanOrEquals(max).isTruthy) return min;
if (min.greaterThanOrEquals(number).isTruthy) return min;
if (number.greaterThanOrEquals(max).isTruthy) return max;
return number;
});
final _floor = _numberFunction("floor", (value) => value.floor().toDouble());
final _max = _function("max", r"$numbers...", (arguments) {
SassNumber? max;
for (var value in arguments[0].asList) {
var number = value.assertNumber();
if (max == null || max.lessThan(number).isTruthy) max = number;
}
if (max != null) return max;
throw SassScriptException("At least one argument must be passed.");
});
final _min = _function("min", r"$numbers...", (arguments) {
SassNumber? min;
for (var value in arguments[0].asList) {
var number = value.assertNumber();
if (min == null || min.greaterThan(number).isTruthy) min = number;
}
if (min != null) return min;
throw SassScriptException("At least one argument must be passed.");
});
final _round = _numberFunction("round", (number) => number.round().toDouble());
///
/// Distance functions
///
final _abs = _numberFunction("abs", (value) => value.abs());
final _hypot = _function("hypot", r"$numbers...", (arguments) {
var numbers =
arguments[0].asList.map((argument) => argument.assertNumber()).toList();
if (numbers.isEmpty) {
throw SassScriptException("At least one argument must be passed.");
}
var subtotal = 0.0;
for (var i = 0; i < numbers.length; i++) {
var number = numbers[i];
var value = number.convertValueToMatch(
numbers[0], "numbers[${i + 1}]", "numbers[1]");
subtotal += math.pow(value, 2);
}
return SassNumber.withUnits(math.sqrt(subtotal),
numeratorUnits: numbers[0].numeratorUnits,
denominatorUnits: numbers[0].denominatorUnits);
});
///
/// Exponential functions
///
final _log = _function("log", r"$number, $base: null", (arguments) {
var number = arguments[0].assertNumber("number");
if (number.hasUnits) {
throw SassScriptException("\$number: Expected $number to have no units.");
} else if (arguments[1] == sassNull) {
return SassNumber(math.log(number.value));
}
var base = arguments[1].assertNumber("base");
if (base.hasUnits) {
throw SassScriptException("\$base: Expected $base to have no units.");
} else {
return SassNumber(math.log(number.value) / math.log(base.value));
}
});
final _pow = _function("pow", r"$base, $exponent", (arguments) {
var base = arguments[0].assertNumber("base");
var exponent = arguments[1].assertNumber("exponent");
if (base.hasUnits) {
throw SassScriptException("\$base: Expected $base to have no units.");
} else if (exponent.hasUnits) {
throw SassScriptException(
"\$exponent: Expected $exponent to have no units.");
} else {
return SassNumber(math.pow(base.value, exponent.value));
}
});
final _sqrt = _function("sqrt", r"$number", (arguments) {
var number = arguments[0].assertNumber("number");
if (number.hasUnits) {
throw SassScriptException("\$number: Expected $number to have no units.");
} else {
return SassNumber(math.sqrt(number.value));
}
});
///
/// Trigonometric functions
///
final _acos = _function("acos", r"$number", (arguments) {
var number = arguments[0].assertNumber("number");
if (number.hasUnits) {
throw SassScriptException("\$number: Expected $number to have no units.");
} else {
return SassNumber.withUnits(math.acos(number.value) * 180 / math.pi,
numeratorUnits: ['deg']);
}
});
final _asin = _function("asin", r"$number", (arguments) {
var number = arguments[0].assertNumber("number");
if (number.hasUnits) {
throw SassScriptException("\$number: Expected $number to have no units.");
} else {
return SassNumber.withUnits(math.asin(number.value) * 180 / math.pi,
numeratorUnits: ['deg']);
}
});
final _atan = _function("atan", r"$number", (arguments) {
var number = arguments[0].assertNumber("number");
if (number.hasUnits) {
throw SassScriptException("\$number: Expected $number to have no units.");
} else {
return SassNumber.withUnits(math.atan(number.value) * 180 / math.pi,
numeratorUnits: ['deg']);
}
});
final _atan2 = _function("atan2", r"$y, $x", (arguments) {
var y = arguments[0].assertNumber("y");
var x = arguments[1].assertNumber("x");
return SassNumber.withUnits(
math.atan2(y.value, x.convertValueToMatch(y, 'x', 'y')) * 180 / math.pi,
numeratorUnits: ['deg']);
});
final _cos = _function(
"cos",
r"$number",
(arguments) => SassNumber(math.cos(arguments[0]
.assertNumber("number")
.coerceValueToUnit("rad", "number"))));
final _sin = _function(
"sin",
r"$number",
(arguments) => SassNumber(math.sin(arguments[0]
.assertNumber("number")
.coerceValueToUnit("rad", "number"))));
final _tan = _function(
"tan",
r"$number",
(arguments) => SassNumber(math.tan(arguments[0]
.assertNumber("number")
.coerceValueToUnit("rad", "number"))));
///
/// Unit functions
///
final _compatible = _function("compatible", r"$number1, $number2", (arguments) {
var number1 = arguments[0].assertNumber("number1");
var number2 = arguments[1].assertNumber("number2");
return SassBoolean(number1.isComparableTo(number2));
});
final _isUnitless = _function("is-unitless", r"$number", (arguments) {
var number = arguments[0].assertNumber("number");
return SassBoolean(!number.hasUnits);
});
final _unit = _function("unit", r"$number", (arguments) {
var number = arguments[0].assertNumber("number");
return SassString(number.unitString, quotes: true);
});
///
/// Other functions
///
final _percentage = _function("percentage", r"$number", (arguments) {
var number = arguments[0].assertNumber("number");
number.assertNoUnits("number");
return SassNumber(number.value * 100, '%');
});
final _random = math.Random();
final _randomFunction = _function("random", r"$limit: null", (arguments) {
if (arguments[0] == sassNull) return SassNumber(_random.nextDouble());
var limit = arguments[0].assertNumber("limit");
if (limit.hasUnits) {
warn(
"math.random() will no longer ignore \$limit units ($limit) in a "
"future release.\n"
"\n"
"Recommendation: "
"math.random(math.div(\$limit, 1${limit.unitString})) * 1${limit.unitString}\n"
"\n"
"To preserve current behavior: "
"math.random(math.div(\$limit, 1${limit.unitString}))\n"
"\n"
"More info: https://sass-lang.com/d/random-with-units",
);
}
var limitScalar = limit.assertInt("limit");
if (limitScalar < 1) {
throw SassScriptException("\$limit: Must be greater than 0, was $limit.");
}
return SassNumber(_random.nextInt(limitScalar) + 1);
});
final _div = _function("div", r"$number1, $number2", (arguments) {
var number1 = arguments[0];
var number2 = arguments[1];
if (number1 is! SassNumber || number2 is! SassNumber) {
warn("math.div() will only support number arguments in a future release.\n"
"Use list.slash() instead for a slash separator.");
}
return number1.dividedBy(number2);
});
///
/// Helpers
///
/// Returns a [Callable] named [name] that transforms a number's value
/// using [transform] and preserves its units.
BuiltInCallable _numberFunction(String name, double transform(double value)) {
return _function(name, r"$number", (arguments) {
var number = arguments[0].assertNumber("number");
return SassNumber.withUnits(transform(number.value),
numeratorUnits: number.numeratorUnits,
denominatorUnits: number.denominatorUnits);
});
}
/// Like [_function.function], but always sets the URL to `sass:math`.
BuiltInCallable _function(
String name, String arguments, Value callback(List<Value> arguments)) =>
BuiltInCallable.function(name, arguments, callback, url: "sass:math");