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1580 lines (1375 loc) · 79.1 KB
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/// <reference path="utilities.ts"/>
/// <reference path="parser.ts"/>
/* @internal */
namespace ts {
export let bindTime = 0;
export const enum ModuleInstanceState {
NonInstantiated = 0,
Instantiated = 1,
ConstEnumOnly = 2
}
const enum Reachability {
Unintialized = 1 << 0,
Reachable = 1 << 1,
Unreachable = 1 << 2,
ReportedUnreachable = 1 << 3
}
function or(state1: Reachability, state2: Reachability): Reachability {
return (state1 | state2) & Reachability.Reachable
? Reachability.Reachable
: (state1 & state2) & Reachability.ReportedUnreachable
? Reachability.ReportedUnreachable
: Reachability.Unreachable;
}
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) && !(node.flags & NodeFlags.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 start = new Date().getTime();
binder(file, options);
bindTime += new Date().getTime() - start;
}
function createBinder(): (file: SourceFile, options: CompilerOptions) => void {
let file: SourceFile;
let options: CompilerOptions;
let parent: Node;
let container: Node;
let blockScopeContainer: Node;
let lastContainer: Node;
let seenThisKeyword: boolean;
// state used by reachability checks
let hasExplicitReturn: boolean;
let currentReachabilityState: Reachability;
let labelStack: Reachability[];
let labelIndexMap: Map<number>;
let implicitLabels: number[];
// 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>;
function bindSourceFile(f: SourceFile, opts: CompilerOptions) {
file = f;
options = opts;
inStrictMode = !!file.externalModuleIndicator;
classifiableNames = {};
Symbol = objectAllocator.getSymbolConstructor();
if (!file.locals) {
bind(file);
file.symbolCount = symbolCount;
file.classifiableNames = classifiableNames;
}
file = undefined;
options = undefined;
parent = undefined;
container = undefined;
blockScopeContainer = undefined;
lastContainer = undefined;
seenThisKeyword = false;
hasExplicitReturn = false;
labelStack = undefined;
labelIndexMap = undefined;
implicitLabels = undefined;
}
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 (node.kind === SyntaxKind.ModuleDeclaration && node.name.kind === SyntaxKind.StringLiteral) {
return `"${(<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:
// Binary expression case is for JS module 'module.exports = expr'
return "export=";
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.ClassDeclaration:
return node.flags & NodeFlags.Default ? "default" : undefined;
}
}
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 = node.flags & NodeFlags.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 (declaration.flags & NodeFlags.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 = getCombinedNodeFlags(node) & NodeFlags.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.
if (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 chilren, 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 accidently 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 savedReachabilityState: Reachability;
let savedLabelStack: Reachability[];
let savedLabels: Map<number>;
let savedImplicitLabels: number[];
let savedHasExplicitReturn: boolean;
const kind = node.kind;
let flags = node.flags;
// reset all reachability check related flags on node (for incremental scenarios)
flags &= ~NodeFlags.ReachabilityCheckFlags;
if (kind === SyntaxKind.InterfaceDeclaration) {
seenThisKeyword = false;
}
const saveState = kind === SyntaxKind.SourceFile || kind === SyntaxKind.ModuleBlock || isFunctionLikeKind(kind);
if (saveState) {
savedReachabilityState = currentReachabilityState;
savedLabelStack = labelStack;
savedLabels = labelIndexMap;
savedImplicitLabels = implicitLabels;
savedHasExplicitReturn = hasExplicitReturn;
currentReachabilityState = Reachability.Reachable;
hasExplicitReturn = false;
labelStack = labelIndexMap = implicitLabels = undefined;
}
bindReachableStatement(node);
if (currentReachabilityState === Reachability.Reachable && 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;
}
node.flags = flags;
if (saveState) {
hasExplicitReturn = savedHasExplicitReturn;
currentReachabilityState = savedReachabilityState;
labelStack = savedLabelStack;
labelIndexMap = savedLabels;
implicitLabels = savedImplicitLabels;
}
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;
default:
forEachChild(node, bind);
break;
}
}
function bindWhileStatement(n: WhileStatement): void {
const preWhileState =
n.expression.kind === SyntaxKind.FalseKeyword ? Reachability.Unreachable : currentReachabilityState;
const postWhileState =
n.expression.kind === SyntaxKind.TrueKeyword ? Reachability.Unreachable : currentReachabilityState;
// bind expressions (don't affect reachability)
bind(n.expression);
currentReachabilityState = preWhileState;
const postWhileLabel = pushImplicitLabel();
bind(n.statement);
popImplicitLabel(postWhileLabel, postWhileState);
}
function bindDoStatement(n: DoStatement): void {
const preDoState = currentReachabilityState;
const postDoLabel = pushImplicitLabel();
bind(n.statement);
const postDoState = n.expression.kind === SyntaxKind.TrueKeyword ? Reachability.Unreachable : preDoState;
popImplicitLabel(postDoLabel, postDoState);
// bind expressions (don't affect reachability)
bind(n.expression);
}
function bindForStatement(n: ForStatement): void {
const preForState = currentReachabilityState;
const postForLabel = pushImplicitLabel();
// bind expressions (don't affect reachability)
bind(n.initializer);
bind(n.condition);
bind(n.incrementor);
bind(n.statement);
// for statement is considered infinite when it condition is either omitted or is true keyword
// - for(..;;..)
// - for(..;true;..)
const isInfiniteLoop = (!n.condition || n.condition.kind === SyntaxKind.TrueKeyword);
const postForState = isInfiniteLoop ? Reachability.Unreachable : preForState;
popImplicitLabel(postForLabel, postForState);
}
function bindForInOrForOfStatement(n: ForInStatement | ForOfStatement): void {
const preStatementState = currentReachabilityState;
const postStatementLabel = pushImplicitLabel();
// bind expressions (don't affect reachability)
bind(n.initializer);
bind(n.expression);
bind(n.statement);
popImplicitLabel(postStatementLabel, preStatementState);
}
function bindIfStatement(n: IfStatement): void {
// denotes reachability state when entering 'thenStatement' part of the if statement:
// i.e. if condition is false then thenStatement is unreachable
const ifTrueState = n.expression.kind === SyntaxKind.FalseKeyword ? Reachability.Unreachable : currentReachabilityState;
// denotes reachability state when entering 'elseStatement':
// i.e. if condition is true then elseStatement is unreachable
const ifFalseState = n.expression.kind === SyntaxKind.TrueKeyword ? Reachability.Unreachable : currentReachabilityState;
currentReachabilityState = ifTrueState;
// bind expression (don't affect reachability)
bind(n.expression);
bind(n.thenStatement);
if (n.elseStatement) {
const preElseState = currentReachabilityState;
currentReachabilityState = ifFalseState;
bind(n.elseStatement);
currentReachabilityState = or(currentReachabilityState, preElseState);
}
else {
currentReachabilityState = or(currentReachabilityState, ifFalseState);
}
}
function bindReturnOrThrow(n: ReturnStatement | ThrowStatement): void {
// bind expression (don't affect reachability)
bind(n.expression);
if (n.kind === SyntaxKind.ReturnStatement) {
hasExplicitReturn = true;
}
currentReachabilityState = Reachability.Unreachable;
}
function bindBreakOrContinueStatement(n: BreakOrContinueStatement): void {
// call bind on label (don't affect reachability)
bind(n.label);
// for continue case touch label so it will be marked a used
const isValidJump = jumpToLabel(n.label, n.kind === SyntaxKind.BreakStatement ? currentReachabilityState : Reachability.Unreachable);
if (isValidJump) {
currentReachabilityState = Reachability.Unreachable;
}
}
function bindTryStatement(n: TryStatement): void {
// catch\finally blocks has the same reachability as try block
const preTryState = currentReachabilityState;
bind(n.tryBlock);
const postTryState = currentReachabilityState;
currentReachabilityState = preTryState;
bind(n.catchClause);
const postCatchState = currentReachabilityState;
currentReachabilityState = preTryState;
bind(n.finallyBlock);
// post catch/finally state is reachable if
// - post try state is reachable - control flow can fall out of try block
// - post catch state is reachable - control flow can fall out of catch block
currentReachabilityState = or(postTryState, postCatchState);
}
function bindSwitchStatement(n: SwitchStatement): void {
const preSwitchState = currentReachabilityState;
const postSwitchLabel = pushImplicitLabel();
// bind expression (don't affect reachability)
bind(n.expression);
bind(n.caseBlock);
const hasDefault = forEach(n.caseBlock.clauses, c => c.kind === SyntaxKind.DefaultClause);
// post switch state is unreachable if switch is exaustive (has a default case ) and does not have fallthrough from the last case
const postSwitchState = hasDefault && currentReachabilityState !== Reachability.Reachable ? Reachability.Unreachable : preSwitchState;
popImplicitLabel(postSwitchLabel, postSwitchState);
}
function bindCaseBlock(n: CaseBlock): void {
const startState = currentReachabilityState;
for (const clause of n.clauses) {
currentReachabilityState = startState;
bind(clause);
if (clause.statements.length && currentReachabilityState === Reachability.Reachable && options.noFallthroughCasesInSwitch) {
errorOnFirstToken(clause, Diagnostics.Fallthrough_case_in_switch);
}
}
}
function bindLabeledStatement(n: LabeledStatement): void {
// call bind on label (don't affect reachability)
bind(n.label);
const ok = pushNamedLabel(n.label);
bind(n.statement);
if (ok) {
popNamedLabel(n.label, currentReachabilityState);
}
}
function getContainerFlags(node: Node): ContainerFlags {
switch (node.kind) {
case SyntaxKind.ClassExpression:
case SyntaxKind.ClassDeclaration:
case SyntaxKind.InterfaceDeclaration:
case SyntaxKind.EnumDeclaration:
case SyntaxKind.TypeLiteral:
case SyntaxKind.ObjectLiteralExpression:
return ContainerFlags.IsContainer;
case SyntaxKind.CallSignature:
case SyntaxKind.ConstructSignature:
case SyntaxKind.IndexSignature:
case SyntaxKind.MethodDeclaration:
case SyntaxKind.MethodSignature:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.Constructor:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.FunctionType:
case SyntaxKind.ConstructorType:
case SyntaxKind.FunctionExpression:
case SyntaxKind.ArrowFunction:
case SyntaxKind.ModuleDeclaration:
case SyntaxKind.SourceFile:
case SyntaxKind.TypeAliasDeclaration:
return ContainerFlags.IsContainerWithLocals;
case SyntaxKind.CatchClause:
case SyntaxKind.ForStatement:
case SyntaxKind.ForInStatement:
case SyntaxKind.ForOfStatement:
case SyntaxKind.CaseBlock:
return ContainerFlags.IsBlockScopedContainer;
case SyntaxKind.Block:
// do not treat blocks directly inside a function as a block-scoped-container.
// Locals that reside in this block should go to the function locals. Othewise 'x'
// would not appear to be a redeclaration of a block scoped local in the following
// example:
//
// function foo() {
// var x;
// let x;
// }
//
// If we placed 'var x' into the function locals and 'let x' into the locals of
// the block, then there would be no collision.
//
// By not creating a new block-scoped-container here, we ensure that both 'var x'
// and 'let x' go into the Function-container's locals, and we do get a collision
// conflict.
return isFunctionLike(node.parent) ? ContainerFlags.None : ContainerFlags.IsBlockScopedContainer;
}
return ContainerFlags.None;
}
function addToContainerChain(next: Node) {
if (lastContainer) {
lastContainer.nextContainer = next;
}
lastContainer = next;
}
function declareSymbolAndAddToSymbolTable(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags): void {
// Just call this directly so that the return type of this function stays "void".
declareSymbolAndAddToSymbolTableWorker(node, symbolFlags, symbolExcludes);
}
function declareSymbolAndAddToSymbolTableWorker(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags): Symbol {
switch (container.kind) {
// Modules, source files, and classes need specialized handling for how their
// members are declared (for example, a member of a class will go into a specific
// symbol table depending on if it is static or not). We defer to specialized
// handlers to take care of declaring these child members.
case SyntaxKind.ModuleDeclaration:
return declareModuleMember(node, symbolFlags, symbolExcludes);
case SyntaxKind.SourceFile:
return declareSourceFileMember(node, symbolFlags, symbolExcludes);
case SyntaxKind.ClassExpression:
case SyntaxKind.ClassDeclaration:
return declareClassMember(node, symbolFlags, symbolExcludes);
case SyntaxKind.EnumDeclaration:
return declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes);
case SyntaxKind.TypeLiteral:
case SyntaxKind.ObjectLiteralExpression:
case SyntaxKind.InterfaceDeclaration:
// Interface/Object-types always have their children added to the 'members' of
// their container. They are only accessible through an instance of their
// container, and are never in scope otherwise (even inside the body of the
// object / type / interface declaring them). An exception is type parameters,
// which are in scope without qualification (similar to 'locals').
return declareSymbol(container.symbol.members, container.symbol, node, symbolFlags, symbolExcludes);
case SyntaxKind.FunctionType:
case SyntaxKind.ConstructorType:
case SyntaxKind.CallSignature:
case SyntaxKind.ConstructSignature:
case SyntaxKind.IndexSignature:
case SyntaxKind.MethodDeclaration:
case SyntaxKind.MethodSignature:
case SyntaxKind.Constructor:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.FunctionExpression:
case SyntaxKind.ArrowFunction:
case SyntaxKind.TypeAliasDeclaration:
// All the children of these container types are never visible through another
// symbol (i.e. through another symbol's 'exports' or 'members'). Instead,
// they're only accessed 'lexically' (i.e. from code that exists underneath
// their container in the tree. To accomplish this, we simply add their declared
// symbol to the 'locals' of the container. These symbols can then be found as
// the type checker walks up the containers, checking them for matching names.
return declareSymbol(container.locals, undefined, node, symbolFlags, symbolExcludes);
}
}
function declareClassMember(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags) {
return node.flags & NodeFlags.Static
? declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes)
: declareSymbol(container.symbol.members, container.symbol, node, symbolFlags, symbolExcludes);
}
function declareSourceFileMember(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags) {
return isExternalModule(file)
? declareModuleMember(node, symbolFlags, symbolExcludes)
: declareSymbol(file.locals, undefined, node, symbolFlags, symbolExcludes);
}
function hasExportDeclarations(node: ModuleDeclaration | SourceFile): boolean {
const body = node.kind === SyntaxKind.SourceFile ? node : (<ModuleDeclaration>node).body;
if (body.kind === SyntaxKind.SourceFile || body.kind === SyntaxKind.ModuleBlock) {
for (const stat of (<Block>body).statements) {
if (stat.kind === SyntaxKind.ExportDeclaration || stat.kind === SyntaxKind.ExportAssignment) {
return true;
}
}
}
return false;
}
function setExportContextFlag(node: ModuleDeclaration | SourceFile) {
// A declaration source file or ambient module declaration that contains no export declarations (but possibly regular
// declarations with export modifiers) is an export context in which declarations are implicitly exported.
if (isInAmbientContext(node) && !hasExportDeclarations(node)) {
node.flags |= NodeFlags.ExportContext;
}
else {
node.flags &= ~NodeFlags.ExportContext;
}
}
function bindModuleDeclaration(node: ModuleDeclaration) {
setExportContextFlag(node);
if (node.name.kind === SyntaxKind.StringLiteral) {
declareSymbolAndAddToSymbolTable(node, SymbolFlags.ValueModule, SymbolFlags.ValueModuleExcludes);
}
else {
const state = getModuleInstanceState(node);
if (state === ModuleInstanceState.NonInstantiated) {
declareSymbolAndAddToSymbolTable(node, SymbolFlags.NamespaceModule, SymbolFlags.NamespaceModuleExcludes);
}
else {
declareSymbolAndAddToSymbolTable(node, SymbolFlags.ValueModule, SymbolFlags.ValueModuleExcludes);
if (node.symbol.flags & (SymbolFlags.Function | SymbolFlags.Class | SymbolFlags.RegularEnum)) {
// if module was already merged with some function, class or non-const enum
// treat is a non-const-enum-only
node.symbol.constEnumOnlyModule = false;
}
else {
const currentModuleIsConstEnumOnly = state === ModuleInstanceState.ConstEnumOnly;
if (node.symbol.constEnumOnlyModule === undefined) {
// non-merged case - use the current state
node.symbol.constEnumOnlyModule = currentModuleIsConstEnumOnly;
}
else {
// merged case: module is const enum only if all its pieces are non-instantiated or const enum
node.symbol.constEnumOnlyModule = node.symbol.constEnumOnlyModule && currentModuleIsConstEnumOnly;
}
}
}
}
}
function bindFunctionOrConstructorType(node: SignatureDeclaration) {
// For a given function symbol "<...>(...) => T" we want to generate a symbol identical
// to the one we would get for: { <...>(...): T }
//
// We do that by making an anonymous type literal symbol, and then setting the function
// symbol as its sole member. To the rest of the system, this symbol will be indistinguishable
// from an actual type literal symbol you would have gotten had you used the long form.
const symbol = createSymbol(SymbolFlags.Signature, getDeclarationName(node));
addDeclarationToSymbol(symbol, node, SymbolFlags.Signature);
const typeLiteralSymbol = createSymbol(SymbolFlags.TypeLiteral, "__type");
addDeclarationToSymbol(typeLiteralSymbol, node, SymbolFlags.TypeLiteral);
typeLiteralSymbol.members = { [symbol.name]: symbol };
}
function bindObjectLiteralExpression(node: ObjectLiteralExpression) {
const enum ElementKind {
Property = 1,
Accessor = 2
}
if (inStrictMode) {
const seen: Map<ElementKind> = {};
for (const prop of node.properties) {
if (prop.name.kind !== SyntaxKind.Identifier) {
continue;
}
const identifier = <Identifier>prop.name;
// ECMA-262 11.1.5 Object Initialiser
// If previous is not undefined then throw a SyntaxError exception if any of the following conditions are true
// a.This production is contained in strict code and IsDataDescriptor(previous) is true and
// IsDataDescriptor(propId.descriptor) is true.
// b.IsDataDescriptor(previous) is true and IsAccessorDescriptor(propId.descriptor) is true.
// c.IsAccessorDescriptor(previous) is true and IsDataDescriptor(propId.descriptor) is true.
// d.IsAccessorDescriptor(previous) is true and IsAccessorDescriptor(propId.descriptor) is true
// and either both previous and propId.descriptor have[[Get]] fields or both previous and propId.descriptor have[[Set]] fields
const currentKind = prop.kind === SyntaxKind.PropertyAssignment || prop.kind === SyntaxKind.ShorthandPropertyAssignment || prop.kind === SyntaxKind.MethodDeclaration
? ElementKind.Property
: ElementKind.Accessor;
const existingKind = seen[identifier.text];
if (!existingKind) {
seen[identifier.text] = currentKind;
continue;
}
if (currentKind === ElementKind.Property && existingKind === ElementKind.Property) {
const span = getErrorSpanForNode(file, identifier);
file.bindDiagnostics.push(createFileDiagnostic(file, span.start, span.length,
Diagnostics.An_object_literal_cannot_have_multiple_properties_with_the_same_name_in_strict_mode));
}
}
}
return bindAnonymousDeclaration(node, SymbolFlags.ObjectLiteral, "__object");
}
function bindAnonymousDeclaration(node: Declaration, symbolFlags: SymbolFlags, name: string) {
const symbol = createSymbol(symbolFlags, name);
addDeclarationToSymbol(symbol, node, symbolFlags);
}
function bindBlockScopedDeclaration(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags) {
switch (blockScopeContainer.kind) {
case SyntaxKind.ModuleDeclaration:
declareModuleMember(node, symbolFlags, symbolExcludes);
break;
case SyntaxKind.SourceFile:
if (isExternalModule(<SourceFile>container)) {
declareModuleMember(node, symbolFlags, symbolExcludes);
break;
}
// fall through.
default:
if (!blockScopeContainer.locals) {
blockScopeContainer.locals = {};
addToContainerChain(blockScopeContainer);
}
declareSymbol(blockScopeContainer.locals, undefined, node, symbolFlags, symbolExcludes);
}
}
function bindBlockScopedVariableDeclaration(node: Declaration) {
bindBlockScopedDeclaration(node, SymbolFlags.BlockScopedVariable, SymbolFlags.BlockScopedVariableExcludes);
}
// The binder visits every node in the syntax tree so it is a convenient place to perform a single localized
// check for reserved words used as identifiers in strict mode code.
function checkStrictModeIdentifier(node: Identifier) {
if (inStrictMode &&
node.originalKeywordKind >= SyntaxKind.FirstFutureReservedWord &&
node.originalKeywordKind <= SyntaxKind.LastFutureReservedWord &&
!isIdentifierName(node)) {
// Report error only if there are no parse errors in file
if (!file.parseDiagnostics.length) {
file.bindDiagnostics.push(createDiagnosticForNode(node,
getStrictModeIdentifierMessage(node), declarationNameToString(node)));
}
}
}
function getStrictModeIdentifierMessage(node: Node) {
// Provide specialized messages to help the user understand why we think they're in
// strict mode.
if (getContainingClass(node)) {
return Diagnostics.Identifier_expected_0_is_a_reserved_word_in_strict_mode_Class_definitions_are_automatically_in_strict_mode;
}
if (file.externalModuleIndicator) {
return Diagnostics.Identifier_expected_0_is_a_reserved_word_in_strict_mode_Modules_are_automatically_in_strict_mode;
}
return Diagnostics.Identifier_expected_0_is_a_reserved_word_in_strict_mode;
}
function checkStrictModeBinaryExpression(node: BinaryExpression) {
if (inStrictMode && isLeftHandSideExpression(node.left) && isAssignmentOperator(node.operatorToken.kind)) {
// ECMA 262 (Annex C) The identifier eval or arguments may not appear as the LeftHandSideExpression of an
// Assignment operator(11.13) or of a PostfixExpression(11.3)
checkStrictModeEvalOrArguments(node, <Identifier>node.left);
}
}
function checkStrictModeCatchClause(node: CatchClause) {
// It is a SyntaxError if a TryStatement with a Catch occurs within strict code and the Identifier of the
// Catch production is eval or arguments
if (inStrictMode && node.variableDeclaration) {
checkStrictModeEvalOrArguments(node, node.variableDeclaration.name);
}
}
function checkStrictModeDeleteExpression(node: DeleteExpression) {
// Grammar checking
if (inStrictMode && node.expression.kind === SyntaxKind.Identifier) {