Merge branch 'master' into errorReportingInJsFile

src/compiler/program.ts

@@ -239,11 +239,11 @@ namespace ts {
                 const { line, character } = getLineAndCharacterOfPosition(diagnostic.file, diagnostic.start);
                 const fileName = diagnostic.file.fileName;
                 const relativeFileName = convertToRelativePath(fileName, host.getCurrentDirectory(), fileName => host.getCanonicalFileName(fileName));
-                output += `${ relativeFileName }(${ line + 1 },${ character + 1 }): `;
+                output += `${relativeFileName}(${line + 1},${character + 1}): `;
             }
 
             const category = DiagnosticCategory[diagnostic.category].toLowerCase();
-            output += `${ category } TS${ diagnostic.code }: ${ flattenDiagnosticMessageText(diagnostic.messageText, host.getNewLine()) }${ host.getNewLine() }`;
+            output += `${category} TS${diagnostic.code}: ${flattenDiagnosticMessageText(diagnostic.messageText, host.getNewLine())}${host.getNewLine()}`;
         }
         return output;
     }
@@ -420,6 +420,7 @@ namespace ts {
             getTypeCount: () => getDiagnosticsProducingTypeChecker().getTypeCount(),
             getFileProcessingDiagnostics: () => fileProcessingDiagnostics,
             getResolvedTypeReferenceDirectives: () => resolvedTypeReferenceDirectives,
+            isSourceFileFromExternalLibrary,
             dropDiagnosticsProducingTypeChecker
         };
 
@@ -462,6 +463,130 @@ namespace ts {
             return classifiableNames;
         }
 
+        interface OldProgramState {
+            program: Program;
+            file: SourceFile;
+            modifiedFilePaths: Path[];
+        }
+
+        function resolveModuleNamesReusingOldState(moduleNames: string[], containingFile: string, file: SourceFile, oldProgramState?: OldProgramState) {
+            if (!oldProgramState && !file.ambientModuleNames.length) {
+                // if old program state is not supplied and file does not contain locally defined ambient modules
+                // then the best we can do is fallback to the default logic
+                return resolveModuleNamesWorker(moduleNames, containingFile);
+            }
+
+            // at this point we know that either 
+            // - file has local declarations for ambient modules
+            // OR
+            // - old program state is available
+            // OR
+            // - both of items above
+            // With this it is possible that we can tell how some module names from the initial list will be resolved
+            // without doing actual resolution (in particular if some name was resolved to ambient module).
+            // Such names should be excluded from the list of module names that will be provided to `resolveModuleNamesWorker`
+            // since we don't want to resolve them again.
+
+            // this is a list of modules for which we cannot predict resolution so they should be actually resolved
+            let unknownModuleNames: string[];
+            // this is a list of combined results assembles from predicted and resolved results.
+            // Order in this list matches the order in the original list of module names `moduleNames` which is important
+            // so later we can split results to resolutions of modules and resolutions of module augmentations.
+            let result: ResolvedModuleFull[];
+            // a transient placeholder that is used to mark predicted resolution in the result list
+            const predictedToResolveToAmbientModuleMarker: ResolvedModuleFull = <any>{};
+
+            for (let i = 0; i < moduleNames.length; i++) {
+                const moduleName = moduleNames[i];
+                // module name is known to be resolved to ambient module if
+                // - module name is contained in the list of ambient modules that are locally declared in the file
+                // - in the old program module name was resolved to ambient module whose declaration is in non-modified file
+                //   (so the same module declaration will land in the new program)
+                let isKnownToResolveToAmbientModule = false;
+                if (contains(file.ambientModuleNames, moduleName)) {
+                    isKnownToResolveToAmbientModule = true;
+                    if (isTraceEnabled(options, host)) {
+                        trace(host, Diagnostics.Module_0_was_resolved_as_locally_declared_ambient_module_in_file_1, moduleName, containingFile);
+                    }
+                }
+                else {
+                    isKnownToResolveToAmbientModule = checkModuleNameResolvedToAmbientModuleInNonModifiedFile(moduleName, oldProgramState);
+                }
+
+                if (isKnownToResolveToAmbientModule) {
+                    if (!unknownModuleNames) {
+                        // found a first module name for which result can be prediced
+                        // this means that this module name should not be passed to `resolveModuleNamesWorker`.
+                        // We'll use a separate list for module names that are definitely unknown.
+                        result = new Array(moduleNames.length);
+                        // copy all module names that appear before the current one in the list
+                        // since they are known to be unknown
+                        unknownModuleNames = moduleNames.slice(0, i);
+                    }
+                    // mark prediced resolution in the result list
+                    result[i] = predictedToResolveToAmbientModuleMarker;
+                }
+                else if (unknownModuleNames) {
+                    // found unknown module name and we are already using separate list for those - add it to the list
+                    unknownModuleNames.push(moduleName);
+                }
+            }
+
+            if (!unknownModuleNames) {
+                // we've looked throught the list but have not seen any predicted resolution
+                // use default logic
+                return resolveModuleNamesWorker(moduleNames, containingFile);
+            }
+
+            const resolutions = unknownModuleNames.length
+                ? resolveModuleNamesWorker(unknownModuleNames, containingFile)
+                : emptyArray;
+
+            // combine results of resolutions and predicted results
+            let j = 0;
+            for (let i = 0; i < result.length; i++) {
+                if (result[i] == predictedToResolveToAmbientModuleMarker) {
+                    result[i] = undefined;
+                }
+                else {
+                    result[i] = resolutions[j];
+                    j++;
+                }
+            }
+            Debug.assert(j === resolutions.length);
+            return result;
+
+            function checkModuleNameResolvedToAmbientModuleInNonModifiedFile(moduleName: string, oldProgramState?: OldProgramState): boolean {
+                if (!oldProgramState) {
+                    return false;
+                }
+                const resolutionToFile = getResolvedModule(oldProgramState.file, moduleName);
+                if (resolutionToFile) {
+                    // module used to be resolved to file - ignore it
+                    return false;
+                }
+                const ambientModule = oldProgram.getTypeChecker().tryFindAmbientModuleWithoutAugmentations(moduleName);
+                if (!(ambientModule && ambientModule.declarations)) {
+                    return false;
+                }
+
+                // at least one of declarations should come from non-modified source file
+                const firstUnmodifiedFile = forEach(ambientModule.declarations, d => {
+                    const f = getSourceFileOfNode(d);
+                    return !contains(oldProgramState.modifiedFilePaths, f.path) && f;
+                });
+
+                if (!firstUnmodifiedFile) {
+                    return false;
+                }
+
+                if (isTraceEnabled(options, host)) {
+                    trace(host, Diagnostics.Module_0_was_resolved_as_ambient_module_declared_in_1_since_this_file_was_not_modified, moduleName, firstUnmodifiedFile.fileName);
+                }
+                return true;
+            }
+        }
+
         function tryReuseStructureFromOldProgram(): boolean {
             if (!oldProgram) {
                 return false;
@@ -489,7 +614,7 @@ namespace ts {
             // check if program source files has changed in the way that can affect structure of the program
             const newSourceFiles: SourceFile[] = [];
             const filePaths: Path[] = [];
-            const modifiedSourceFiles: SourceFile[] = [];
+            const modifiedSourceFiles: { oldFile: SourceFile, newFile: SourceFile }[] = [];
 
             for (const oldSourceFile of oldProgram.getSourceFiles()) {
                 let newSourceFile = host.getSourceFileByPath
@@ -532,29 +657,8 @@ namespace ts {
                         return false;
                     }
 
-                    const newSourceFilePath = getNormalizedAbsolutePath(newSourceFile.fileName, currentDirectory);
-                    if (resolveModuleNamesWorker) {
-                        const moduleNames = map(concatenate(newSourceFile.imports, newSourceFile.moduleAugmentations), getTextOfLiteral);
-                        const resolutions = resolveModuleNamesWorker(moduleNames, newSourceFilePath);
-                        // ensure that module resolution results are still correct
-                        const resolutionsChanged = hasChangesInResolutions(moduleNames, resolutions, oldSourceFile.resolvedModules, moduleResolutionIsEqualTo);
-                        if (resolutionsChanged) {
-                            return false;
-                        }
-                    }
-                    if (resolveTypeReferenceDirectiveNamesWorker) {
-                        const typesReferenceDirectives = map(newSourceFile.typeReferenceDirectives, x => x.fileName);
-                        const resolutions = resolveTypeReferenceDirectiveNamesWorker(typesReferenceDirectives, newSourceFilePath);
-                        // ensure that types resolutions are still correct
-                        const resolutionsChanged = hasChangesInResolutions(typesReferenceDirectives, resolutions, oldSourceFile.resolvedTypeReferenceDirectiveNames, typeDirectiveIsEqualTo);
-                        if (resolutionsChanged) {
-                            return false;
-                        }
-                    }
-                    // pass the cache of module/types resolutions from the old source file
-                    newSourceFile.resolvedModules = oldSourceFile.resolvedModules;
-                    newSourceFile.resolvedTypeReferenceDirectiveNames = oldSourceFile.resolvedTypeReferenceDirectiveNames;
-                    modifiedSourceFiles.push(newSourceFile);
+                    // tentatively approve the file
+                    modifiedSourceFiles.push({ oldFile: oldSourceFile, newFile: newSourceFile });
                 }
                 else {
                     // file has no changes - use it as is
@@ -565,6 +669,33 @@ namespace ts {
                 newSourceFiles.push(newSourceFile);
             }
 
+            const modifiedFilePaths = modifiedSourceFiles.map(f => f.newFile.path);
+            // try to verify results of module resolution 
+            for (const { oldFile: oldSourceFile, newFile: newSourceFile } of modifiedSourceFiles) {
+                const newSourceFilePath = getNormalizedAbsolutePath(newSourceFile.fileName, currentDirectory);
+                if (resolveModuleNamesWorker) {
+                    const moduleNames = map(concatenate(newSourceFile.imports, newSourceFile.moduleAugmentations), getTextOfLiteral);
+                    const resolutions = resolveModuleNamesReusingOldState(moduleNames, newSourceFilePath, newSourceFile, { file: oldSourceFile, program: oldProgram, modifiedFilePaths });
+                    // ensure that module resolution results are still correct
+                    const resolutionsChanged = hasChangesInResolutions(moduleNames, resolutions, oldSourceFile.resolvedModules, moduleResolutionIsEqualTo);
+                    if (resolutionsChanged) {
+                        return false;
+                    }
+                }
+                if (resolveTypeReferenceDirectiveNamesWorker) {
+                    const typesReferenceDirectives = map(newSourceFile.typeReferenceDirectives, x => x.fileName);
+                    const resolutions = resolveTypeReferenceDirectiveNamesWorker(typesReferenceDirectives, newSourceFilePath);
+                    // ensure that types resolutions are still correct
+                    const resolutionsChanged = hasChangesInResolutions(typesReferenceDirectives, resolutions, oldSourceFile.resolvedTypeReferenceDirectiveNames, typeDirectiveIsEqualTo);
+                    if (resolutionsChanged) {
+                        return false;
+                    }
+                }
+                // pass the cache of module/types resolutions from the old source file
+                newSourceFile.resolvedModules = oldSourceFile.resolvedModules;
+                newSourceFile.resolvedTypeReferenceDirectiveNames = oldSourceFile.resolvedTypeReferenceDirectiveNames;
+            }
+
             // update fileName -> file mapping
             for (let i = 0, len = newSourceFiles.length; i < len; i++) {
                 filesByName.set(filePaths[i], newSourceFiles[i]);
@@ -574,7 +705,7 @@ namespace ts {
             fileProcessingDiagnostics = oldProgram.getFileProcessingDiagnostics();
 
             for (const modifiedFile of modifiedSourceFiles) {
-                fileProcessingDiagnostics.reattachFileDiagnostics(modifiedFile);
+                fileProcessingDiagnostics.reattachFileDiagnostics(modifiedFile.newFile);
             }
             resolvedTypeReferenceDirectives = oldProgram.getResolvedTypeReferenceDirectives();
             oldProgram.structureIsReused = true;
@@ -592,13 +723,17 @@ namespace ts {
                 getSourceFile: program.getSourceFile,
                 getSourceFileByPath: program.getSourceFileByPath,
                 getSourceFiles: program.getSourceFiles,
-                isSourceFileFromExternalLibrary: (file: SourceFile) => !!sourceFilesFoundSearchingNodeModules[file.path],
+                isSourceFileFromExternalLibrary,
                 writeFile: writeFileCallback || (
                     (fileName, data, writeByteOrderMark, onError, sourceFiles) => host.writeFile(fileName, data, writeByteOrderMark, onError, sourceFiles)),
                 isEmitBlocked,
             };
         }
 
+        function isSourceFileFromExternalLibrary(file: SourceFile): boolean {
+            return sourceFilesFoundSearchingNodeModules[file.path];
+        }
+
         function getDiagnosticsProducingTypeChecker() {
             return diagnosticsProducingTypeChecker || (diagnosticsProducingTypeChecker = createTypeChecker(program, /*produceDiagnostics:*/ true));
         }
@@ -998,9 +1133,11 @@ namespace ts {
 
             const isJavaScriptFile = isSourceFileJavaScript(file);
             const isExternalModuleFile = isExternalModule(file);
+            const isDtsFile = isDeclarationFile(file);
 
             let imports: LiteralExpression[];
             let moduleAugmentations: LiteralExpression[];
+            let ambientModules: string[];
 
             // If we are importing helpers, we need to add a synthetic reference to resolve the
             // helpers library.
@@ -1022,6 +1159,7 @@ namespace ts {
 
             file.imports = imports || emptyArray;
             file.moduleAugmentations = moduleAugmentations || emptyArray;
+            file.ambientModuleNames = ambientModules || emptyArray;
 
             return;
 
@@ -1057,6 +1195,10 @@ namespace ts {
                                 (moduleAugmentations || (moduleAugmentations = [])).push(moduleName);
                             }
                             else if (!inAmbientModule) {
+                                if (isDtsFile) {
+                                    // for global .d.ts files record name of ambient module
+                                    (ambientModules || (ambientModules = [])).push(moduleName.text);
+                                }
                                 // An AmbientExternalModuleDeclaration declares an external module.
                                 // This type of declaration is permitted only in the global module.
                                 // The StringLiteral must specify a top - level external module name.
@@ -1302,7 +1444,7 @@ namespace ts {
             if (file.imports.length || file.moduleAugmentations.length) {
                 file.resolvedModules = createMap<ResolvedModuleFull>();
                 const moduleNames = map(concatenate(file.imports, file.moduleAugmentations), getTextOfLiteral);
-                const resolutions = resolveModuleNamesWorker(moduleNames, getNormalizedAbsolutePath(file.fileName, currentDirectory));
+                const resolutions = resolveModuleNamesReusingOldState(moduleNames, getNormalizedAbsolutePath(file.fileName, currentDirectory), file);
                 Debug.assert(resolutions.length === moduleNames.length);
                 for (let i = 0; i < moduleNames.length; i++) {
                     const resolution = resolutions[i];
@@ -1552,13 +1694,24 @@ namespace ts {
                     const emitFilePath = toPath(emitFileName, currentDirectory, getCanonicalFileName);
                     // Report error if the output overwrites input file
                     if (filesByName.contains(emitFilePath)) {
-                        createEmitBlockingDiagnostics(emitFileName, Diagnostics.Cannot_write_file_0_because_it_would_overwrite_input_file);
+                        if (options.noEmitOverwritenFiles && !options.out && !options.outDir && !options.outFile) {
+                            blockEmittingOfFile(emitFileName);
+                        }
+                        else {
+                            let chain: DiagnosticMessageChain;
+                            if (!options.configFilePath) {
+                                // The program is from either an inferred project or an external project
+                                chain = chainDiagnosticMessages(/*details*/ undefined, Diagnostics.Adding_a_tsconfig_json_file_will_help_organize_projects_that_contain_both_TypeScript_and_JavaScript_files_Learn_more_at_https_Colon_Slash_Slashaka_ms_Slashtsconfig);
+                            }
+                            chain = chainDiagnosticMessages(chain, Diagnostics.Cannot_write_file_0_because_it_would_overwrite_input_file, emitFileName);
+                            blockEmittingOfFile(emitFileName, createCompilerDiagnosticFromMessageChain(chain));
+                        }
                     }
 
                     // Report error if multiple files write into same file
                     if (emitFilesSeen.contains(emitFilePath)) {
                         // Already seen the same emit file - report error
-                        createEmitBlockingDiagnostics(emitFileName, Diagnostics.Cannot_write_file_0_because_it_would_be_overwritten_by_multiple_input_files);
+                        blockEmittingOfFile(emitFileName, createCompilerDiagnostic(Diagnostics.Cannot_write_file_0_because_it_would_be_overwritten_by_multiple_input_files, emitFileName));
                     }
                     else {
                         emitFilesSeen.set(emitFilePath, true);
@@ -1567,9 +1720,11 @@ namespace ts {
             }
         }
 
-        function createEmitBlockingDiagnostics(emitFileName: string, message: DiagnosticMessage) {
+        function blockEmittingOfFile(emitFileName: string, diag?: Diagnostic) {
             hasEmitBlockingDiagnostics.set(toPath(emitFileName, currentDirectory, getCanonicalFileName), true);
-            programDiagnostics.add(createCompilerDiagnostic(message, emitFileName));
+            if (diag) {
+                programDiagnostics.add(diag);
+            }
         }
     }