Skip to content

Commit

Permalink
Merge pull request #4788 from Microsoft/reachabilityChecks
Browse files Browse the repository at this point in the history 
initial revision of reachability checks
  • Loading branch information
@vladima
vladima committed Nov 2, 2015
2 parents 3e63144 + 3f11c0b commit fb15e9c
Show file tree
Hide file tree
Showing 415 changed files with 5,603 additions and 4,337 deletions.
484 changes: 454 additions & 30 deletions src/compiler/binder.ts
View file

Large diffs are not rendered by default.

56 changes: 24 additions & 32 deletions src/compiler/checker.ts
View file
Original file line number Diff line number Diff line change
Expand Up @@ -160,6 +160,8 @@ namespace ts {
let getGlobalPromiseConstructorLikeType: () => ObjectType;
let getGlobalThenableType: () => ObjectType;

let jsxElementClassType: Type;

let tupleTypes: Map<TupleType> = {};
let unionTypes: Map<UnionType> = {};
let intersectionTypes: Map<IntersectionType> = {};
Expand Down Expand Up @@ -7874,7 +7876,6 @@ namespace ts {
return prop || unknownSymbol;
}

let jsxElementClassType: Type = undefined;
function getJsxGlobalElementClassType(): Type {
if (!jsxElementClassType) {
jsxElementClassType = getExportedTypeFromNamespace(JsxNames.JSX, JsxNames.ElementClass);
Expand Down Expand Up @@ -9620,21 +9621,11 @@ namespace ts {
return aggregatedTypes;
}

function bodyContainsAReturnStatement(funcBody: Block) {
return forEachReturnStatement(funcBody, returnStatement => {
return true;
});
}

function bodyContainsSingleThrowStatement(body: Block) {
return (body.statements.length === 1) && (body.statements[0].kind === SyntaxKind.ThrowStatement);
}

// TypeScript Specification 1.0 (6.3) - July 2014
// An explicitly typed function whose return type isn't the Void or the Any type
// must have at least one return statement somewhere in its body.
// An exception to this rule is if the function implementation consists of a single 'throw' statement.
function checkIfNonVoidFunctionHasReturnExpressionsOrSingleThrowStatment(func: FunctionLikeDeclaration, returnType: Type): void {
function checkAllCodePathsInNonVoidFunctionReturnOrThrow(func: FunctionLikeDeclaration, returnType: Type): void {
if (!produceDiagnostics) {
return;
}
Expand All @@ -9645,26 +9636,20 @@ namespace ts {
}

// If all we have is a function signature, or an arrow function with an expression body, then there is nothing to check.
if (nodeIsMissing(func.body) || func.body.kind !== SyntaxKind.Block) {
// also if HasImplicitReturnValue flags is not set this means that all codepaths in function body end with return of throw
if (nodeIsMissing(func.body) || func.body.kind !== SyntaxKind.Block || !(func.flags & NodeFlags.HasImplicitReturn)) {
return;
}

let bodyBlock = <Block>func.body;

// Ensure the body has at least one return expression.
if (bodyContainsAReturnStatement(bodyBlock)) {
return;
if (func.flags & NodeFlags.HasExplicitReturn) {
if (compilerOptions.noImplicitReturns) {
error(func.type, Diagnostics.Not_all_code_paths_return_a_value);
}
}

// If there are no return expressions, then we need to check if
// the function body consists solely of a throw statement;
// this is to make an exception for unimplemented functions.
if (bodyContainsSingleThrowStatement(bodyBlock)) {
return;
else {
// This function does not conform to the specification.
error(func.type, Diagnostics.A_function_whose_declared_type_is_neither_void_nor_any_must_return_a_value);
}

// This function does not conform to the specification.
error(func.type, Diagnostics.A_function_whose_declared_type_is_neither_void_nor_any_must_return_a_value_or_consist_of_a_single_throw_statement);
}

function checkFunctionExpressionOrObjectLiteralMethod(node: FunctionExpression | MethodDeclaration, contextualMapper?: TypeMapper): Type {
Expand Down Expand Up @@ -9744,7 +9729,7 @@ namespace ts {
}

if (returnType && !node.asteriskToken) {
checkIfNonVoidFunctionHasReturnExpressionsOrSingleThrowStatment(node, isAsync ? promisedType : returnType);
checkAllCodePathsInNonVoidFunctionReturnOrThrow(node, isAsync ? promisedType : returnType);
}

if (node.body) {
Expand Down Expand Up @@ -10945,8 +10930,15 @@ namespace ts {
checkGrammarFunctionLikeDeclaration(node) || checkGrammarAccessor(node) || checkGrammarComputedPropertyName(node.name);

if (node.kind === SyntaxKind.GetAccessor) {
if (!isInAmbientContext(node) && nodeIsPresent(node.body) && !(bodyContainsAReturnStatement(<Block>node.body) || bodyContainsSingleThrowStatement(<Block>node.body))) {
error(node.name, Diagnostics.A_get_accessor_must_return_a_value_or_consist_of_a_single_throw_statement);
if (!isInAmbientContext(node) && nodeIsPresent(node.body) && (node.flags & NodeFlags.HasImplicitReturn)) {
if (node.flags & NodeFlags.HasExplicitReturn) {
if (compilerOptions.noImplicitReturns) {
error(node.name, Diagnostics.Not_all_code_paths_return_a_value);
}
}
else {
error(node.name, Diagnostics.A_get_accessor_must_return_a_value);
}
}
}

Expand Down Expand Up @@ -11877,7 +11869,7 @@ namespace ts {
promisedType = checkAsyncFunctionReturnType(node);
}

checkIfNonVoidFunctionHasReturnExpressionsOrSingleThrowStatment(node, isAsync ? promisedType : returnType);
checkAllCodePathsInNonVoidFunctionReturnOrThrow(node, isAsync ? promisedType : returnType);
}

if (produceDiagnostics && !node.type) {
Expand Down Expand Up @@ -14915,7 +14907,7 @@ namespace ts {
function initializeTypeChecker() {
// Bind all source files and propagate errors
forEach(host.getSourceFiles(), file => {
bindSourceFile(file);
bindSourceFile(file, compilerOptions);
});

// Initialize global symbol table
Expand Down
22 changes: 21 additions & 1 deletion src/compiler/commandLineParser.ts
View file
Original file line number Diff line number Diff line change
Expand Up @@ -248,11 +248,31 @@ namespace ts {
description: Diagnostics.Specifies_module_resolution_strategy_Colon_node_Node_js_or_classic_TypeScript_pre_1_6,
error: Diagnostics.Argument_for_moduleResolution_option_must_be_node_or_classic,
},
{
name: "allowUnusedLabels",
type: "boolean",
description: Diagnostics.Do_not_report_errors_on_unused_labels
},
{
name: "noImplicitReturns",
type: "boolean",
description: Diagnostics.Report_error_when_not_all_code_paths_in_function_return_a_value
},
{
name: "noFallthroughCasesInSwitch",
type: "boolean",
description: Diagnostics.Report_errors_for_fallthrough_cases_in_switch_statement
},
{
name: "allowUnreachableCode",
type: "boolean",
description: Diagnostics.Do_not_report_errors_on_unreachable_code
},
{
name: "forceConsistentCasingInFileNames",
type: "boolean",
description: Diagnostics.Disallow_inconsistently_cased_references_to_the_same_file
},
}
];

/* @internal */
Expand Down
38 changes: 34 additions & 4 deletions src/compiler/diagnosticMessages.json
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1012,7 +1012,7 @@
"category": "Error",
"code": 2354
},
"A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement.": {
"A function whose declared type is neither 'void' nor 'any' must return a value.": {
"category": "Error",
"code": 2355
},
Expand Down Expand Up @@ -1096,7 +1096,7 @@
"category": "Error",
"code": 2377
},
"A 'get' accessor must return a value or consist of a single 'throw' statement.": {
"A 'get' accessor must return a value.": {
"category": "Error",
"code": 2378
},
Expand Down Expand Up @@ -2298,6 +2298,22 @@
"category": "Message",
"code": 6073
},
"Do not report errors on unused labels.": {
"category": "Message",
"code": 6074
},
"Report error when not all code paths in function return a value.": {
"category": "Message",
"code": 6075
},
"Report errors for fallthrough cases in switch statement.": {
"category": "Message",
"code": 6076
},
"Do not report errors on unreachable code.": {
"category": "Message",
"code": 6077
},
"Variable '{0}' implicitly has an '{1}' type.": {
"category": "Error",
"code": 7005
Expand Down Expand Up @@ -2366,8 +2382,22 @@
"category": "Error",
"code": 7026
},


"Unreachable code detected.": {
"category": "Error",
"code": 7027
},
"Unused label.": {
"category": "Error",
"code": 7028
},
"Fallthrough case in switch.": {
"category": "Error",
"code": 7029
},
"Not all code paths return a value.": {
"category": "Error",
"code": 7030
},
"You cannot rename this element.": {
"category": "Error",
"code": 8000
Expand Down
12 changes: 6 additions & 6 deletions src/compiler/emitter.ts
View file
Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,12 @@ namespace ts {

type DependencyGroup = Array<ImportDeclaration | ImportEqualsDeclaration | ExportDeclaration>;

const enum Jump {
Break = 1 << 1,
Continue = 1 << 2,
Return = 1 << 3
}

let entities: Map<number> = {
"quot": 0x0022,
"amp": 0x0026,
Expand Down Expand Up @@ -371,12 +377,6 @@ var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, Promi
return true;
}

const enum Jump {
Break = 1 << 1,
Continue = 1 << 2,
Return = 1 << 3
}

interface ConvertedLoopState {
/*
* set of labels that occured inside the converted loop
Expand Down
47 changes: 27 additions & 20 deletions src/compiler/types.ts
View file
Original file line number Diff line number Diff line change
Expand Up @@ -367,28 +367,31 @@ namespace ts {

export const enum NodeFlags {
None = 0,
Export = 0x00000001, // Declarations
Ambient = 0x00000002, // Declarations
Public = 0x00000010, // Property/Method
Private = 0x00000020, // Property/Method
Protected = 0x00000040, // Property/Method
Static = 0x00000080, // Property/Method
Abstract = 0x00000100, // Class/Method/ConstructSignature
Async = 0x00000200, // Property/Method/Function
Default = 0x00000400, // Function/Class (export default declaration)
MultiLine = 0x00000800, // Multi-line array or object literal
Synthetic = 0x00001000, // Synthetic node (for full fidelity)
DeclarationFile = 0x00002000, // Node is a .d.ts file
Let = 0x00004000, // Variable declaration
Const = 0x00008000, // Variable declaration
OctalLiteral = 0x00010000, // Octal numeric literal
Namespace = 0x00020000, // Namespace declaration
ExportContext = 0x00040000, // Export context (initialized by binding)
ContainsThis = 0x00080000, // Interface contains references to "this"

Export = 1 << 1, // Declarations
Ambient = 1 << 2, // Declarations
Public = 1 << 3, // Property/Method
Private = 1 << 4, // Property/Method
Protected = 1 << 5, // Property/Method
Static = 1 << 6, // Property/Method
Abstract = 1 << 7, // Class/Method/ConstructSignature
Async = 1 << 8, // Property/Method/Function
Default = 1 << 9, // Function/Class (export default declaration)
MultiLine = 1 << 10, // Multi-line array or object literal
Synthetic = 1 << 11, // Synthetic node (for full fidelity)
DeclarationFile = 1 << 12, // Node is a .d.ts file
Let = 1 << 13, // Variable declaration
Const = 1 << 14, // Variable declaration
OctalLiteral = 1 << 15, // Octal numeric literal
Namespace = 1 << 16, // Namespace declaration
ExportContext = 1 << 17, // Export context (initialized by binding)
ContainsThis = 1 << 18, // Interface contains references to "this"
HasImplicitReturn = 1 << 19, // If function implicitly returns on one of codepaths (initialized by binding)
HasExplicitReturn = 1 << 20, // If function has explicit reachable return on one of codepaths (initialized by binding)
Modifier = Export | Ambient | Public | Private | Protected | Static | Abstract | Default | Async,
AccessibilityModifier = Public | Private | Protected,
BlockScoped = Let | Const
BlockScoped = Let | Const,

ReachabilityCheckFlags = HasImplicitReturn | HasExplicitReturn
}

/* @internal */
Expand Down Expand Up @@ -2098,6 +2101,10 @@ namespace ts {
experimentalDecorators?: boolean;
emitDecoratorMetadata?: boolean;
moduleResolution?: ModuleResolutionKind;
allowUnusedLabels?: boolean;
allowUnreachableCode?: boolean;
noImplicitReturns?: boolean;
noFallthroughCasesInSwitch?: boolean;
forceConsistentCasingInFileNames?: boolean;
/* @internal */ stripInternal?: boolean;

Expand Down
39 changes: 20 additions & 19 deletions src/compiler/utilities.ts
View file
Original file line number Diff line number Diff line change
Expand Up @@ -622,25 +622,26 @@ namespace ts {
}

export function isFunctionLike(node: Node): node is FunctionLikeDeclaration {
if (node) {
switch (node.kind) {
case SyntaxKind.Constructor:
case SyntaxKind.FunctionExpression:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.ArrowFunction:
case SyntaxKind.MethodDeclaration:
case SyntaxKind.MethodSignature:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.CallSignature:
case SyntaxKind.ConstructSignature:
case SyntaxKind.IndexSignature:
case SyntaxKind.FunctionType:
case SyntaxKind.ConstructorType:
return true;
}
return node && isFunctionLikeKind(node.kind);
}

export function isFunctionLikeKind(kind: SyntaxKind): boolean {
switch (kind) {
case SyntaxKind.Constructor:
case SyntaxKind.FunctionExpression:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.ArrowFunction:
case SyntaxKind.MethodDeclaration:
case SyntaxKind.MethodSignature:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.CallSignature:
case SyntaxKind.ConstructSignature:
case SyntaxKind.IndexSignature:
case SyntaxKind.FunctionType:
case SyntaxKind.ConstructorType:
return true;
}
return false;
}

export function introducesArgumentsExoticObject(node: Node) {
Expand Down Expand Up @@ -1236,7 +1237,7 @@ namespace ts {
case SyntaxKind.LabeledStatement:
case SyntaxKind.ReturnStatement:
case SyntaxKind.SwitchStatement:
case SyntaxKind.ThrowKeyword:
case SyntaxKind.ThrowStatement:
case SyntaxKind.TryStatement:
case SyntaxKind.VariableStatement:
case SyntaxKind.WhileStatement:
Expand Down
5 changes: 1 addition & 4 deletions src/services/breakpoints.ts
View file
Original file line number Diff line number Diff line change
Expand Up @@ -446,7 +446,7 @@ namespace ts.BreakpointResolver {
// fall through.

case SyntaxKind.CatchClause:
return spanInNode(lastOrUndefined((<Block>node.parent).statements));;
return spanInNode(lastOrUndefined((<Block>node.parent).statements));

case SyntaxKind.CaseBlock:
// breakpoint in last statement of the last clause
Expand Down Expand Up @@ -493,9 +493,6 @@ namespace ts.BreakpointResolver {
default:
return spanInNode(node.parent);
}

// Default to parent node
return spanInNode(node.parent);
}

function spanInColonToken(node: Node): TextSpan {
Expand Down
1 change: 0 additions & 1 deletion src/services/formatting/smartIndenter.ts
View file
Original file line number Diff line number Diff line change
Expand Up @@ -360,7 +360,6 @@ namespace ts.formatting {
return node;
}
}
return node;
}
}

Expand Down
Loading

0 comments on commit fb15e9c

Please sign in to comment.