forked from microsoft/TypeScript
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathbinder.ts
More file actions
2917 lines (2555 loc) · 142 KB
/
Copy pathbinder.ts
File metadata and controls
2917 lines (2555 loc) · 142 KB
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
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/// <reference path="utilities.ts"/>
/// <reference path="parser.ts"/>
/* @internal */
namespace ts {
export const enum ModuleInstanceState {
NonInstantiated = 0,
Instantiated = 1,
ConstEnumOnly = 2
}
interface ActiveLabel {
name: string;
breakTarget: FlowLabel;
continueTarget: FlowLabel;
referenced: boolean;
}
export function getModuleInstanceState(node: Node): ModuleInstanceState {
// A module is uninstantiated if it contains only
// 1. interface declarations, type alias declarations
if (node.kind === SyntaxKind.InterfaceDeclaration || node.kind === SyntaxKind.TypeAliasDeclaration) {
return ModuleInstanceState.NonInstantiated;
}
// 2. const enum declarations
else if (isConstEnumDeclaration(node)) {
return ModuleInstanceState.ConstEnumOnly;
}
// 3. non-exported import declarations
else if ((node.kind === SyntaxKind.ImportDeclaration || node.kind === SyntaxKind.ImportEqualsDeclaration) && !(hasModifier(node, ModifierFlags.Export))) {
return ModuleInstanceState.NonInstantiated;
}
// 4. other uninstantiated module declarations.
else if (node.kind === SyntaxKind.ModuleBlock) {
let state = ModuleInstanceState.NonInstantiated;
forEachChild(node, n => {
switch (getModuleInstanceState(n)) {
case ModuleInstanceState.NonInstantiated:
// child is non-instantiated - continue searching
return false;
case ModuleInstanceState.ConstEnumOnly:
// child is const enum only - record state and continue searching
state = ModuleInstanceState.ConstEnumOnly;
return false;
case ModuleInstanceState.Instantiated:
// child is instantiated - record state and stop
state = ModuleInstanceState.Instantiated;
return true;
}
});
return state;
}
else if (node.kind === SyntaxKind.ModuleDeclaration) {
return getModuleInstanceState((<ModuleDeclaration>node).body);
}
else {
return ModuleInstanceState.Instantiated;
}
}
const enum ContainerFlags {
// The current node is not a container, and no container manipulation should happen before
// recursing into it.
None = 0,
// The current node is a container. It should be set as the current container (and block-
// container) before recursing into it. The current node does not have locals. Examples:
//
// Classes, ObjectLiterals, TypeLiterals, Interfaces...
IsContainer = 1 << 0,
// The current node is a block-scoped-container. It should be set as the current block-
// container before recursing into it. Examples:
//
// Blocks (when not parented by functions), Catch clauses, For/For-in/For-of statements...
IsBlockScopedContainer = 1 << 1,
HasLocals = 1 << 2,
// If the current node is a container that also container that also contains locals. Examples:
//
// Functions, Methods, Modules, Source-files.
IsContainerWithLocals = IsContainer | HasLocals
}
const binder = createBinder();
export function bindSourceFile(file: SourceFile, options: CompilerOptions) {
const bindStart = performance.mark();
binder(file, options);
performance.measure("bindTime", bindStart);
}
function createBinder(): (file: SourceFile, options: CompilerOptions) => void {
let file: SourceFile;
let options: CompilerOptions;
let languageVersion: ScriptTarget;
let parent: Node;
let container: Node;
let blockScopeContainer: Node;
let lastContainer: Node;
let seenThisKeyword: boolean;
// state used by reachability checks
let hasExplicitReturn: boolean;
let currentFlow: FlowNode;
let currentBreakTarget: FlowLabel;
let currentContinueTarget: FlowLabel;
let currentTrueTarget: FlowLabel;
let currentFalseTarget: FlowLabel;
let preSwitchCaseFlow: FlowNode;
let activeLabels: ActiveLabel[];
// state used for emit helpers
let hasClassExtends: boolean;
let hasAsyncFunctions: boolean;
let hasDecorators: boolean;
let hasParameterDecorators: boolean;
let hasJsxSpreadAttribute: boolean;
// If this file is an external module, then it is automatically in strict-mode according to
// ES6. If it is not an external module, then we'll determine if it is in strict mode or
// not depending on if we see "use strict" in certain places (or if we hit a class/namespace).
let inStrictMode: boolean;
let symbolCount = 0;
let Symbol: { new (flags: SymbolFlags, name: string): Symbol };
let classifiableNames: Map<string>;
const unreachableFlow: FlowNode = { flags: FlowFlags.Unreachable };
const reportedUnreachableFlow: FlowNode = { flags: FlowFlags.Unreachable };
// state used to aggregate transform flags during bind.
let subtreeTransformFlags: TransformFlags = TransformFlags.None;
let skipTransformFlagAggregation: boolean;
function bindSourceFile(f: SourceFile, opts: CompilerOptions) {
file = f;
options = opts;
languageVersion = getEmitScriptTarget(options);
inStrictMode = !!file.externalModuleIndicator;
classifiableNames = {};
symbolCount = 0;
skipTransformFlagAggregation = isDeclarationFile(file);
Symbol = objectAllocator.getSymbolConstructor();
if (!file.locals) {
bind(file);
file.symbolCount = symbolCount;
file.classifiableNames = classifiableNames;
}
file = undefined;
options = undefined;
languageVersion = undefined;
parent = undefined;
container = undefined;
blockScopeContainer = undefined;
lastContainer = undefined;
seenThisKeyword = false;
hasExplicitReturn = false;
currentFlow = undefined;
currentBreakTarget = undefined;
currentContinueTarget = undefined;
currentTrueTarget = undefined;
currentFalseTarget = undefined;
activeLabels = undefined;
hasClassExtends = false;
hasAsyncFunctions = false;
hasDecorators = false;
hasParameterDecorators = false;
subtreeTransformFlags = TransformFlags.None;
hasJsxSpreadAttribute = false;
}
return bindSourceFile;
function createSymbol(flags: SymbolFlags, name: string): Symbol {
symbolCount++;
return new Symbol(flags, name);
}
function addDeclarationToSymbol(symbol: Symbol, node: Declaration, symbolFlags: SymbolFlags) {
symbol.flags |= symbolFlags;
node.symbol = symbol;
if (!symbol.declarations) {
symbol.declarations = [];
}
symbol.declarations.push(node);
if (symbolFlags & SymbolFlags.HasExports && !symbol.exports) {
symbol.exports = {};
}
if (symbolFlags & SymbolFlags.HasMembers && !symbol.members) {
symbol.members = {};
}
if (symbolFlags & SymbolFlags.Value) {
const valueDeclaration = symbol.valueDeclaration;
if (!valueDeclaration ||
(valueDeclaration.kind !== node.kind && valueDeclaration.kind === SyntaxKind.ModuleDeclaration)) {
// other kinds of value declarations take precedence over modules
symbol.valueDeclaration = node;
}
}
}
// Should not be called on a declaration with a computed property name,
// unless it is a well known Symbol.
function getDeclarationName(node: Declaration): string {
if (node.name) {
if (isAmbientModule(node)) {
return isGlobalScopeAugmentation(<ModuleDeclaration>node) ? "__global" : `"${(<LiteralExpression>node.name).text}"`;
}
if (node.name.kind === SyntaxKind.ComputedPropertyName) {
const nameExpression = (<ComputedPropertyName>node.name).expression;
// treat computed property names where expression is string/numeric literal as just string/numeric literal
if (isStringOrNumericLiteral(nameExpression.kind)) {
return (<LiteralExpression>nameExpression).text;
}
Debug.assert(isWellKnownSymbolSyntactically(nameExpression));
return getPropertyNameForKnownSymbolName((<PropertyAccessExpression>nameExpression).name.text);
}
return (<Identifier | LiteralExpression>node.name).text;
}
switch (node.kind) {
case SyntaxKind.Constructor:
return "__constructor";
case SyntaxKind.FunctionType:
case SyntaxKind.CallSignature:
return "__call";
case SyntaxKind.ConstructorType:
case SyntaxKind.ConstructSignature:
return "__new";
case SyntaxKind.IndexSignature:
return "__index";
case SyntaxKind.ExportDeclaration:
return "__export";
case SyntaxKind.ExportAssignment:
return (<ExportAssignment>node).isExportEquals ? "export=" : "default";
case SyntaxKind.BinaryExpression:
switch (getSpecialPropertyAssignmentKind(node)) {
case SpecialPropertyAssignmentKind.ModuleExports:
// module.exports = ...
return "export=";
case SpecialPropertyAssignmentKind.ExportsProperty:
case SpecialPropertyAssignmentKind.ThisProperty:
// exports.x = ... or this.y = ...
return ((node as BinaryExpression).left as PropertyAccessExpression).name.text;
case SpecialPropertyAssignmentKind.PrototypeProperty:
// className.prototype.methodName = ...
return (((node as BinaryExpression).left as PropertyAccessExpression).expression as PropertyAccessExpression).name.text;
}
Debug.fail("Unknown binary declaration kind");
break;
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.ClassDeclaration:
return hasModifier(node, ModifierFlags.Default) ? "default" : undefined;
case SyntaxKind.JSDocFunctionType:
return isJSDocConstructSignature(node) ? "__new" : "__call";
case SyntaxKind.Parameter:
// Parameters with names are handled at the top of this function. Parameters
// without names can only come from JSDocFunctionTypes.
Debug.assert(node.parent.kind === SyntaxKind.JSDocFunctionType);
let functionType = <JSDocFunctionType>node.parent;
let index = indexOf(functionType.parameters, node);
return "p" + index;
}
}
function getDisplayName(node: Declaration): string {
return node.name ? declarationNameToString(node.name) : getDeclarationName(node);
}
/**
* Declares a Symbol for the node and adds it to symbols. Reports errors for conflicting identifier names.
* @param symbolTable - The symbol table which node will be added to.
* @param parent - node's parent declaration.
* @param node - The declaration to be added to the symbol table
* @param includes - The SymbolFlags that node has in addition to its declaration type (eg: export, ambient, etc.)
* @param excludes - The flags which node cannot be declared alongside in a symbol table. Used to report forbidden declarations.
*/
function declareSymbol(symbolTable: SymbolTable, parent: Symbol, node: Declaration, includes: SymbolFlags, excludes: SymbolFlags): Symbol {
Debug.assert(!hasDynamicName(node));
const isDefaultExport = hasModifier(node, ModifierFlags.Default);
// The exported symbol for an export default function/class node is always named "default"
const name = isDefaultExport && parent ? "default" : getDeclarationName(node);
let symbol: Symbol;
if (name !== undefined) {
// Check and see if the symbol table already has a symbol with this name. If not,
// create a new symbol with this name and add it to the table. Note that we don't
// give the new symbol any flags *yet*. This ensures that it will not conflict
// with the 'excludes' flags we pass in.
//
// If we do get an existing symbol, see if it conflicts with the new symbol we're
// creating. For example, a 'var' symbol and a 'class' symbol will conflict within
// the same symbol table. If we have a conflict, report the issue on each
// declaration we have for this symbol, and then create a new symbol for this
// declaration.
//
// If we created a new symbol, either because we didn't have a symbol with this name
// in the symbol table, or we conflicted with an existing symbol, then just add this
// node as the sole declaration of the new symbol.
//
// Otherwise, we'll be merging into a compatible existing symbol (for example when
// you have multiple 'vars' with the same name in the same container). In this case
// just add this node into the declarations list of the symbol.
symbol = hasProperty(symbolTable, name)
? symbolTable[name]
: (symbolTable[name] = createSymbol(SymbolFlags.None, name));
if (name && (includes & SymbolFlags.Classifiable)) {
classifiableNames[name] = name;
}
if (symbol.flags & excludes) {
if (node.name) {
node.name.parent = node;
}
// Report errors every position with duplicate declaration
// Report errors on previous encountered declarations
let message = symbol.flags & SymbolFlags.BlockScopedVariable
? Diagnostics.Cannot_redeclare_block_scoped_variable_0
: Diagnostics.Duplicate_identifier_0;
forEach(symbol.declarations, declaration => {
if (hasModifier(declaration, ModifierFlags.Default)) {
message = Diagnostics.A_module_cannot_have_multiple_default_exports;
}
});
forEach(symbol.declarations, declaration => {
file.bindDiagnostics.push(createDiagnosticForNode(declaration.name || declaration, message, getDisplayName(declaration)));
});
file.bindDiagnostics.push(createDiagnosticForNode(node.name || node, message, getDisplayName(node)));
symbol = createSymbol(SymbolFlags.None, name);
}
}
else {
symbol = createSymbol(SymbolFlags.None, "__missing");
}
addDeclarationToSymbol(symbol, node, includes);
symbol.parent = parent;
return symbol;
}
function declareModuleMember(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags): Symbol {
const hasExportModifier = getCombinedModifierFlags(node) & ModifierFlags.Export;
if (symbolFlags & SymbolFlags.Alias) {
if (node.kind === SyntaxKind.ExportSpecifier || (node.kind === SyntaxKind.ImportEqualsDeclaration && hasExportModifier)) {
return declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes);
}
else {
return declareSymbol(container.locals, undefined, node, symbolFlags, symbolExcludes);
}
}
else {
// Exported module members are given 2 symbols: A local symbol that is classified with an ExportValue,
// ExportType, or ExportContainer flag, and an associated export symbol with all the correct flags set
// on it. There are 2 main reasons:
//
// 1. We treat locals and exports of the same name as mutually exclusive within a container.
// That means the binder will issue a Duplicate Identifier error if you mix locals and exports
// with the same name in the same container.
// TODO: Make this a more specific error and decouple it from the exclusion logic.
// 2. When we checkIdentifier in the checker, we set its resolved symbol to the local symbol,
// but return the export symbol (by calling getExportSymbolOfValueSymbolIfExported). That way
// when the emitter comes back to it, it knows not to qualify the name if it was found in a containing scope.
// NOTE: Nested ambient modules always should go to to 'locals' table to prevent their automatic merge
// during global merging in the checker. Why? The only case when ambient module is permitted inside another module is module augmentation
// and this case is specially handled. Module augmentations should only be merged with original module definition
// and should never be merged directly with other augmentation, and the latter case would be possible if automatic merge is allowed.
if (!isAmbientModule(node) && (hasExportModifier || container.flags & NodeFlags.ExportContext)) {
const exportKind =
(symbolFlags & SymbolFlags.Value ? SymbolFlags.ExportValue : 0) |
(symbolFlags & SymbolFlags.Type ? SymbolFlags.ExportType : 0) |
(symbolFlags & SymbolFlags.Namespace ? SymbolFlags.ExportNamespace : 0);
const local = declareSymbol(container.locals, undefined, node, exportKind, symbolExcludes);
local.exportSymbol = declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes);
node.localSymbol = local;
return local;
}
else {
return declareSymbol(container.locals, undefined, node, symbolFlags, symbolExcludes);
}
}
}
// All container nodes are kept on a linked list in declaration order. This list is used by
// the getLocalNameOfContainer function in the type checker to validate that the local name
// used for a container is unique.
function bindChildren(node: Node) {
// Before we recurse into a node's children, we first save the existing parent, container
// and block-container. Then after we pop out of processing the children, we restore
// these saved values.
const saveParent = parent;
const saveContainer = container;
const savedBlockScopeContainer = blockScopeContainer;
// This node will now be set as the parent of all of its children as we recurse into them.
parent = node;
// Depending on what kind of node this is, we may have to adjust the current container
// and block-container. If the current node is a container, then it is automatically
// considered the current block-container as well. Also, for containers that we know
// may contain locals, we proactively initialize the .locals field. We do this because
// it's highly likely that the .locals will be needed to place some child in (for example,
// a parameter, or variable declaration).
//
// However, we do not proactively create the .locals for block-containers because it's
// totally normal and common for block-containers to never actually have a block-scoped
// variable in them. We don't want to end up allocating an object for every 'block' we
// run into when most of them won't be necessary.
//
// Finally, if this is a block-container, then we clear out any existing .locals object
// it may contain within it. This happens in incremental scenarios. Because we can be
// reusing a node from a previous compilation, that node may have had 'locals' created
// for it. We must clear this so we don't accidentally move any stale data forward from
// a previous compilation.
const containerFlags = getContainerFlags(node);
if (containerFlags & ContainerFlags.IsContainer) {
container = blockScopeContainer = node;
if (containerFlags & ContainerFlags.HasLocals) {
container.locals = {};
}
addToContainerChain(container);
}
else if (containerFlags & ContainerFlags.IsBlockScopedContainer) {
blockScopeContainer = node;
blockScopeContainer.locals = undefined;
}
let savedHasExplicitReturn: boolean;
let savedCurrentFlow: FlowNode;
let savedBreakTarget: FlowLabel;
let savedContinueTarget: FlowLabel;
let savedActiveLabels: ActiveLabel[];
const kind = node.kind;
let flags = node.flags;
// reset all reachability check related flags on node (for incremental scenarios)
flags &= ~NodeFlags.ReachabilityCheckFlags;
// reset all emit helper flags on node (for incremental scenarios)
flags &= ~NodeFlags.EmitHelperFlags;
if (kind === SyntaxKind.InterfaceDeclaration) {
seenThisKeyword = false;
}
const saveState = kind === SyntaxKind.SourceFile || kind === SyntaxKind.ModuleBlock || isFunctionLikeKind(kind);
if (saveState) {
savedHasExplicitReturn = hasExplicitReturn;
savedCurrentFlow = currentFlow;
savedBreakTarget = currentBreakTarget;
savedContinueTarget = currentContinueTarget;
savedActiveLabels = activeLabels;
hasExplicitReturn = false;
currentFlow = { flags: FlowFlags.Start };
currentBreakTarget = undefined;
currentContinueTarget = undefined;
activeLabels = undefined;
}
if (isInJavaScriptFile(node) && node.jsDocComment) {
bind(node.jsDocComment);
}
bindReachableStatement(node);
if (!(currentFlow.flags & FlowFlags.Unreachable) && isFunctionLikeKind(kind) && nodeIsPresent((<FunctionLikeDeclaration>node).body)) {
flags |= NodeFlags.HasImplicitReturn;
if (hasExplicitReturn) {
flags |= NodeFlags.HasExplicitReturn;
}
}
if (kind === SyntaxKind.InterfaceDeclaration) {
flags = seenThisKeyword ? flags | NodeFlags.ContainsThis : flags & ~NodeFlags.ContainsThis;
}
if (kind === SyntaxKind.SourceFile) {
if (hasClassExtends) {
flags |= NodeFlags.HasClassExtends;
}
if (hasDecorators) {
flags |= NodeFlags.HasDecorators;
}
if (hasParameterDecorators) {
flags |= NodeFlags.HasParamDecorators;
}
if (hasAsyncFunctions) {
flags |= NodeFlags.HasAsyncFunctions;
}
if (hasJsxSpreadAttribute) {
flags |= NodeFlags.HasJsxSpreadAttribute;
}
}
node.flags = flags;
if (saveState) {
hasExplicitReturn = savedHasExplicitReturn;
currentFlow = savedCurrentFlow;
currentBreakTarget = savedBreakTarget;
currentContinueTarget = savedContinueTarget;
activeLabels = savedActiveLabels;
}
container = saveContainer;
parent = saveParent;
blockScopeContainer = savedBlockScopeContainer;
}
/**
* Returns true if node and its subnodes were successfully traversed.
* Returning false means that node was not examined and caller needs to dive into the node himself.
*/
function bindReachableStatement(node: Node): void {
if (checkUnreachable(node)) {
forEachChild(node, bind);
return;
}
switch (node.kind) {
case SyntaxKind.WhileStatement:
bindWhileStatement(<WhileStatement>node);
break;
case SyntaxKind.DoStatement:
bindDoStatement(<DoStatement>node);
break;
case SyntaxKind.ForStatement:
bindForStatement(<ForStatement>node);
break;
case SyntaxKind.ForInStatement:
case SyntaxKind.ForOfStatement:
bindForInOrForOfStatement(<ForInStatement | ForOfStatement>node);
break;
case SyntaxKind.IfStatement:
bindIfStatement(<IfStatement>node);
break;
case SyntaxKind.ReturnStatement:
case SyntaxKind.ThrowStatement:
bindReturnOrThrow(<ReturnStatement | ThrowStatement>node);
break;
case SyntaxKind.BreakStatement:
case SyntaxKind.ContinueStatement:
bindBreakOrContinueStatement(<BreakOrContinueStatement>node);
break;
case SyntaxKind.TryStatement:
bindTryStatement(<TryStatement>node);
break;
case SyntaxKind.SwitchStatement:
bindSwitchStatement(<SwitchStatement>node);
break;
case SyntaxKind.CaseBlock:
bindCaseBlock(<CaseBlock>node);
break;
case SyntaxKind.LabeledStatement:
bindLabeledStatement(<LabeledStatement>node);
break;
case SyntaxKind.PrefixUnaryExpression:
bindPrefixUnaryExpressionFlow(<PrefixUnaryExpression>node);
break;
case SyntaxKind.BinaryExpression:
bindBinaryExpressionFlow(<BinaryExpression>node);
break;
case SyntaxKind.DeleteExpression:
bindDeleteExpressionFlow(<DeleteExpression>node);
break;
case SyntaxKind.ConditionalExpression:
bindConditionalExpressionFlow(<ConditionalExpression>node);
break;
case SyntaxKind.VariableDeclaration:
bindVariableDeclarationFlow(<VariableDeclaration>node);
break;
default:
forEachChild(node, bind);
break;
}
}
function isNarrowableReference(expr: Expression): boolean {
return expr.kind === SyntaxKind.Identifier ||
expr.kind === SyntaxKind.ThisKeyword ||
expr.kind === SyntaxKind.PropertyAccessExpression && isNarrowableReference((<PropertyAccessExpression>expr).expression);
}
function isNarrowingExpression(expr: Expression): boolean {
switch (expr.kind) {
case SyntaxKind.Identifier:
case SyntaxKind.ThisKeyword:
case SyntaxKind.PropertyAccessExpression:
return isNarrowableReference(expr);
case SyntaxKind.CallExpression:
return true;
case SyntaxKind.ParenthesizedExpression:
return isNarrowingExpression((<ParenthesizedExpression>expr).expression);
case SyntaxKind.BinaryExpression:
return isNarrowingBinaryExpression(<BinaryExpression>expr);
case SyntaxKind.PrefixUnaryExpression:
return (<PrefixUnaryExpression>expr).operator === SyntaxKind.ExclamationToken && isNarrowingExpression((<PrefixUnaryExpression>expr).operand);
}
return false;
}
function isNarrowingBinaryExpression(expr: BinaryExpression) {
switch (expr.operatorToken.kind) {
case SyntaxKind.EqualsToken:
return isNarrowableReference(expr.left);
case SyntaxKind.EqualsEqualsToken:
case SyntaxKind.ExclamationEqualsToken:
case SyntaxKind.EqualsEqualsEqualsToken:
case SyntaxKind.ExclamationEqualsEqualsToken:
if (isNarrowingExpression(expr.left) && (expr.right.kind === SyntaxKind.NullKeyword || expr.right.kind === SyntaxKind.Identifier)) {
return true;
}
if (expr.left.kind === SyntaxKind.TypeOfExpression && isNarrowingExpression((<TypeOfExpression>expr.left).expression) && expr.right.kind === SyntaxKind.StringLiteral) {
return true;
}
return false;
case SyntaxKind.InstanceOfKeyword:
return isNarrowingExpression(expr.left);
case SyntaxKind.CommaToken:
return isNarrowingExpression(expr.right);
}
return false;
}
function createBranchLabel(): FlowLabel {
return {
flags: FlowFlags.BranchLabel,
antecedents: undefined
};
}
function createLoopLabel(): FlowLabel {
return {
flags: FlowFlags.LoopLabel,
antecedents: undefined
};
}
function setFlowNodeReferenced(flow: FlowNode) {
// On first reference we set the Referenced flag, thereafter we set the Shared flag
flow.flags |= flow.flags & FlowFlags.Referenced ? FlowFlags.Shared : FlowFlags.Referenced;
}
function addAntecedent(label: FlowLabel, antecedent: FlowNode): void {
if (!(antecedent.flags & FlowFlags.Unreachable) && !contains(label.antecedents, antecedent)) {
(label.antecedents || (label.antecedents = [])).push(antecedent);
setFlowNodeReferenced(antecedent);
}
}
function createFlowCondition(flags: FlowFlags, antecedent: FlowNode, expression: Expression): FlowNode {
if (antecedent.flags & FlowFlags.Unreachable) {
return antecedent;
}
if (!expression) {
return flags & FlowFlags.TrueCondition ? antecedent : unreachableFlow;
}
if (expression.kind === SyntaxKind.TrueKeyword && flags & FlowFlags.FalseCondition ||
expression.kind === SyntaxKind.FalseKeyword && flags & FlowFlags.TrueCondition) {
return unreachableFlow;
}
if (!isNarrowingExpression(expression)) {
return antecedent;
}
setFlowNodeReferenced(antecedent);
return <FlowCondition>{
flags,
antecedent,
expression,
};
}
function createFlowAssignment(antecedent: FlowNode, node: Expression | VariableDeclaration | BindingElement): FlowNode {
setFlowNodeReferenced(antecedent);
return <FlowAssignment>{
flags: FlowFlags.Assignment,
antecedent,
node
};
}
function finishFlowLabel(flow: FlowLabel): FlowNode {
const antecedents = flow.antecedents;
if (!antecedents) {
return unreachableFlow;
}
if (antecedents.length === 1) {
return antecedents[0];
}
return flow;
}
function isStatementCondition(node: Node) {
const parent = node.parent;
switch (parent.kind) {
case SyntaxKind.IfStatement:
case SyntaxKind.WhileStatement:
case SyntaxKind.DoStatement:
return (<IfStatement | WhileStatement | DoStatement>parent).expression === node;
case SyntaxKind.ForStatement:
case SyntaxKind.ConditionalExpression:
return (<ForStatement | ConditionalExpression>parent).condition === node;
}
return false;
}
function isLogicalExpression(node: Node) {
while (true) {
if (node.kind === SyntaxKind.ParenthesizedExpression) {
node = (<ParenthesizedExpression>node).expression;
}
else if (node.kind === SyntaxKind.PrefixUnaryExpression && (<PrefixUnaryExpression>node).operator === SyntaxKind.ExclamationToken) {
node = (<PrefixUnaryExpression>node).operand;
}
else {
return node.kind === SyntaxKind.BinaryExpression && (
(<BinaryExpression>node).operatorToken.kind === SyntaxKind.AmpersandAmpersandToken ||
(<BinaryExpression>node).operatorToken.kind === SyntaxKind.BarBarToken);
}
}
}
function isTopLevelLogicalExpression(node: Node): boolean {
while (node.parent.kind === SyntaxKind.ParenthesizedExpression ||
node.parent.kind === SyntaxKind.PrefixUnaryExpression &&
(<PrefixUnaryExpression>node.parent).operator === SyntaxKind.ExclamationToken) {
node = node.parent;
}
return !isStatementCondition(node) && !isLogicalExpression(node.parent);
}
function bindCondition(node: Expression, trueTarget: FlowLabel, falseTarget: FlowLabel) {
const saveTrueTarget = currentTrueTarget;
const saveFalseTarget = currentFalseTarget;
currentTrueTarget = trueTarget;
currentFalseTarget = falseTarget;
bind(node);
currentTrueTarget = saveTrueTarget;
currentFalseTarget = saveFalseTarget;
if (!node || !isLogicalExpression(node)) {
addAntecedent(trueTarget, createFlowCondition(FlowFlags.TrueCondition, currentFlow, node));
addAntecedent(falseTarget, createFlowCondition(FlowFlags.FalseCondition, currentFlow, node));
}
}
function bindIterativeStatement(node: Statement, breakTarget: FlowLabel, continueTarget: FlowLabel): void {
const saveBreakTarget = currentBreakTarget;
const saveContinueTarget = currentContinueTarget;
currentBreakTarget = breakTarget;
currentContinueTarget = continueTarget;
bind(node);
currentBreakTarget = saveBreakTarget;
currentContinueTarget = saveContinueTarget;
}
function bindWhileStatement(node: WhileStatement): void {
const preWhileLabel = createLoopLabel();
const preBodyLabel = createBranchLabel();
const postWhileLabel = createBranchLabel();
addAntecedent(preWhileLabel, currentFlow);
currentFlow = preWhileLabel;
bindCondition(node.expression, preBodyLabel, postWhileLabel);
currentFlow = finishFlowLabel(preBodyLabel);
bindIterativeStatement(node.statement, postWhileLabel, preWhileLabel);
addAntecedent(preWhileLabel, currentFlow);
currentFlow = finishFlowLabel(postWhileLabel);
}
function bindDoStatement(node: DoStatement): void {
const preDoLabel = createLoopLabel();
const preConditionLabel = createBranchLabel();
const postDoLabel = createBranchLabel();
addAntecedent(preDoLabel, currentFlow);
currentFlow = preDoLabel;
bindIterativeStatement(node.statement, postDoLabel, preConditionLabel);
addAntecedent(preConditionLabel, currentFlow);
currentFlow = finishFlowLabel(preConditionLabel);
bindCondition(node.expression, preDoLabel, postDoLabel);
currentFlow = finishFlowLabel(postDoLabel);
}
function bindForStatement(node: ForStatement): void {
const preLoopLabel = createLoopLabel();
const preBodyLabel = createBranchLabel();
const postLoopLabel = createBranchLabel();
bind(node.initializer);
addAntecedent(preLoopLabel, currentFlow);
currentFlow = preLoopLabel;
bindCondition(node.condition, preBodyLabel, postLoopLabel);
currentFlow = finishFlowLabel(preBodyLabel);
bindIterativeStatement(node.statement, postLoopLabel, preLoopLabel);
bind(node.incrementor);
addAntecedent(preLoopLabel, currentFlow);
currentFlow = finishFlowLabel(postLoopLabel);
}
function bindForInOrForOfStatement(node: ForInStatement | ForOfStatement): void {
const preLoopLabel = createLoopLabel();
const postLoopLabel = createBranchLabel();
addAntecedent(preLoopLabel, currentFlow);
currentFlow = preLoopLabel;
bind(node.expression);
addAntecedent(postLoopLabel, currentFlow);
bind(node.initializer);
if (node.initializer.kind !== SyntaxKind.VariableDeclarationList) {
bindAssignmentTargetFlow(<Expression>node.initializer);
}
bindIterativeStatement(node.statement, postLoopLabel, preLoopLabel);
addAntecedent(preLoopLabel, currentFlow);
currentFlow = finishFlowLabel(postLoopLabel);
}
function bindIfStatement(node: IfStatement): void {
const thenLabel = createBranchLabel();
const elseLabel = createBranchLabel();
const postIfLabel = createBranchLabel();
bindCondition(node.expression, thenLabel, elseLabel);
currentFlow = finishFlowLabel(thenLabel);
bind(node.thenStatement);
addAntecedent(postIfLabel, currentFlow);
currentFlow = finishFlowLabel(elseLabel);
bind(node.elseStatement);
addAntecedent(postIfLabel, currentFlow);
currentFlow = finishFlowLabel(postIfLabel);
}
function bindReturnOrThrow(node: ReturnStatement | ThrowStatement): void {
bind(node.expression);
if (node.kind === SyntaxKind.ReturnStatement) {
hasExplicitReturn = true;
}
currentFlow = unreachableFlow;
}
function findActiveLabel(name: string) {
if (activeLabels) {
for (const label of activeLabels) {
if (label.name === name) {
return label;
}
}
}
return undefined;
}
function bindbreakOrContinueFlow(node: BreakOrContinueStatement, breakTarget: FlowLabel, continueTarget: FlowLabel) {
const flowLabel = node.kind === SyntaxKind.BreakStatement ? breakTarget : continueTarget;
if (flowLabel) {
addAntecedent(flowLabel, currentFlow);
currentFlow = unreachableFlow;
}
}
function bindBreakOrContinueStatement(node: BreakOrContinueStatement): void {
bind(node.label);
if (node.label) {
const activeLabel = findActiveLabel(node.label.text);
if (activeLabel) {
activeLabel.referenced = true;
bindbreakOrContinueFlow(node, activeLabel.breakTarget, activeLabel.continueTarget);
}
}
else {
bindbreakOrContinueFlow(node, currentBreakTarget, currentContinueTarget);
}
}
function bindTryStatement(node: TryStatement): void {
const postFinallyLabel = createBranchLabel();
const preTryFlow = currentFlow;
// TODO: Every statement in try block is potentially an exit point!
bind(node.tryBlock);
addAntecedent(postFinallyLabel, currentFlow);
if (node.catchClause) {
currentFlow = preTryFlow;
bind(node.catchClause);
addAntecedent(postFinallyLabel, currentFlow);
}
if (node.finallyBlock) {
currentFlow = preTryFlow;
bind(node.finallyBlock);
}
currentFlow = finishFlowLabel(postFinallyLabel);
}
function bindSwitchStatement(node: SwitchStatement): void {
const postSwitchLabel = createBranchLabel();
bind(node.expression);
const saveBreakTarget = currentBreakTarget;
const savePreSwitchCaseFlow = preSwitchCaseFlow;
currentBreakTarget = postSwitchLabel;
preSwitchCaseFlow = currentFlow;
bind(node.caseBlock);
addAntecedent(postSwitchLabel, currentFlow);
const hasDefault = forEach(node.caseBlock.clauses, c => c.kind === SyntaxKind.DefaultClause);
if (!hasDefault) {
addAntecedent(postSwitchLabel, preSwitchCaseFlow);
}
currentBreakTarget = saveBreakTarget;
preSwitchCaseFlow = savePreSwitchCaseFlow;
currentFlow = finishFlowLabel(postSwitchLabel);
}
function bindCaseBlock(node: CaseBlock): void {
const clauses = node.clauses;
for (let i = 0; i < clauses.length; i++) {
const clause = clauses[i];
if (clause.statements.length) {
if (currentFlow.flags & FlowFlags.Unreachable) {
currentFlow = preSwitchCaseFlow;
}
else {
const preCaseLabel = createBranchLabel();
addAntecedent(preCaseLabel, preSwitchCaseFlow);
addAntecedent(preCaseLabel, currentFlow);
currentFlow = finishFlowLabel(preCaseLabel);
}
bind(clause);
if (!(currentFlow.flags & FlowFlags.Unreachable) && i !== clauses.length - 1 && options.noFallthroughCasesInSwitch) {
errorOnFirstToken(clause, Diagnostics.Fallthrough_case_in_switch);
}
}
else {
bind(clause);
}
}
}
function pushActiveLabel(name: string, breakTarget: FlowLabel, continueTarget: FlowLabel): ActiveLabel {
const activeLabel = {
name,
breakTarget,
continueTarget,
referenced: false
};
(activeLabels || (activeLabels = [])).push(activeLabel);
return activeLabel;
}
function popActiveLabel() {
activeLabels.pop();
}
function bindLabeledStatement(node: LabeledStatement): void {
const preStatementLabel = createLoopLabel();
const postStatementLabel = createBranchLabel();
bind(node.label);
addAntecedent(preStatementLabel, currentFlow);
const activeLabel = pushActiveLabel(node.label.text, postStatementLabel, preStatementLabel);
bind(node.statement);
popActiveLabel();
if (!activeLabel.referenced && !options.allowUnusedLabels) {
file.bindDiagnostics.push(createDiagnosticForNode(node.label, Diagnostics.Unused_label));
}
addAntecedent(postStatementLabel, currentFlow);
currentFlow = finishFlowLabel(postStatementLabel);
}
function bindDestructuringTargetFlow(node: Expression) {
if (node.kind === SyntaxKind.BinaryExpression && (<BinaryExpression>node).operatorToken.kind === SyntaxKind.EqualsToken) {
bindAssignmentTargetFlow((<BinaryExpression>node).left);
}
else {
bindAssignmentTargetFlow(node);
}
}
function bindAssignmentTargetFlow(node: Expression) {
if (isNarrowableReference(node)) {
currentFlow = createFlowAssignment(currentFlow, node);
}
else if (node.kind === SyntaxKind.ArrayLiteralExpression) {
for (const e of (<ArrayLiteralExpression>node).elements) {
if (e.kind === SyntaxKind.SpreadElementExpression) {
bindAssignmentTargetFlow((<SpreadElementExpression>e).expression);
}