Merge branch 'master' into narrow-unknown-with-triple-equals

Author: jack-williams

src/compiler/binder.ts

@@ -735,6 +735,8 @@ namespace ts {
                     return isNarrowingBinaryExpression(<BinaryExpression>expr);
                 case SyntaxKind.PrefixUnaryExpression:
                     return (<PrefixUnaryExpression>expr).operator === SyntaxKind.ExclamationToken && isNarrowingExpression((<PrefixUnaryExpression>expr).operand);
+                case SyntaxKind.TypeOfExpression:
+                    return isNarrowingExpression((<TypeOfExpression>expr).expression);
             }
             return false;
         }

src/compiler/checker.ts

@@ -1843,8 +1843,21 @@ namespace ts {
             if (hasProperty(raw, "files") && !isNullOrUndefined(raw.files)) {
                 if (isArray(raw.files)) {
                     filesSpecs = <ReadonlyArray<string>>raw.files;
-                    if (filesSpecs.length === 0) {
-                        createCompilerDiagnosticOnlyIfJson(Diagnostics.The_files_list_in_config_file_0_is_empty, configFileName || "tsconfig.json");
+                    const hasReferences = hasProperty(raw, "references") && !isNullOrUndefined(raw.references);
+                    const hasZeroOrNoReferences = !hasReferences || raw.references.length === 0;
+                    if (filesSpecs.length === 0 && hasZeroOrNoReferences) {
+                        if (sourceFile) {
+                            const fileName = configFileName || "tsconfig.json";
+                            const diagnosticMessage = Diagnostics.The_files_list_in_config_file_0_is_empty;
+                            const nodeValue = firstDefined(getTsConfigPropArray(sourceFile, "files"), property => property.initializer);
+                            const error = nodeValue
+                                ? createDiagnosticForNodeInSourceFile(sourceFile, nodeValue, diagnosticMessage, fileName)
+                                : createCompilerDiagnostic(diagnosticMessage, fileName);
+                            errors.push(error);
+                        }
+                        else {
+                            createCompilerDiagnosticOnlyIfJson(Diagnostics.The_files_list_in_config_file_0_is_empty, configFileName || "tsconfig.json");
+                        }
                     }
                 }
                 else {
@@ -2067,11 +2080,6 @@ namespace ts {
                                 createDiagnosticForNodeInSourceFile(sourceFile, valueNode, message, arg0)
                         );
                         return;
-                    case "files":
-                        if ((<ReadonlyArray<string>>value).length === 0) {
-                            errors.push(createDiagnosticForNodeInSourceFile(sourceFile, valueNode, Diagnostics.The_files_list_in_config_file_0_is_empty, configFileName || "tsconfig.json"));
-                        }
-                        return;
                 }
             },
             onSetUnknownOptionKeyValueInRoot(key: string, keyNode: PropertyName, _value: CompilerOptionsValue, _valueNode: Expression) {
@@ -2081,6 +2089,7 @@ namespace ts {
             }
         };
         const json = convertToObjectWorker(sourceFile, errors, /*returnValue*/ true, getTsconfigRootOptionsMap(), optionsIterator);
+
         if (!typeAcquisition) {
             if (typingOptionstypeAcquisition) {
                 typeAcquisition = (typingOptionstypeAcquisition.enableAutoDiscovery !== undefined) ?

src/compiler/commandLineParser.ts

@@ -65,6 +65,7 @@ namespace ts {
 
 /* @internal */
 namespace ts {
+    export const emptyArray: never[] = [] as never[];
 
     /** Create a MapLike with good performance. */
     function createDictionaryObject<T>(): MapLike<T> {

src/compiler/core.ts

@@ -835,7 +835,7 @@
         "category": "Error",
         "code": 1253
     },
-    "A 'const' initializer in an ambient context must be a string or numeric literal.": {
+    "A 'const' initializer in an ambient context must be a string or numeric literal or literal enum reference.": {
         "category": "Error",
         "code": 1254
     },
@@ -2088,6 +2088,30 @@
         "category": "Error",
         "code": 2577
     },
+    "Cannot find name '{0}'. Do you need to install type definitions for node? Try `npm i @types/node`.": {
+        "category": "Error",
+        "code": 2580
+    },
+    "Cannot find name '{0}'. Do you need to install type definitions for jQuery? Try `npm i @types/jquery`.": {
+        "category": "Error",
+        "code": 2581
+    },
+    "Cannot find name '{0}'. Do you need to install type definitions for a test runner? Try `npm i @types/jest` or `npm i @types/mocha`.": {
+        "category": "Error",
+        "code": 2582
+    },
+    "Cannot find name '{0}'. Do you need to change your target library? Try changing the `lib` compiler option to es2015 or later.": {
+        "category": "Error",
+        "code": 2583
+    },
+    "Cannot find name '{0}'. Do you need to change your target library? Try changing the `lib` compiler option to include 'dom'.": {
+        "category": "Error",
+        "code": 2584
+    },
+    "'{0}' only refers to a type, but is being used as a value here. Do you need to change your target library? Try changing the `lib` compiler option to es2015 or later.": {
+        "category": "Error",
+        "code": 2585
+    },
     "JSX element attributes type '{0}' may not be a union type.": {
         "category": "Error",
         "code": 2600
@@ -2457,6 +2481,10 @@
         "category": "Error",
         "code": 2733
     },
+    "It is highly likely that you are missing a semicolon.": {
+        "category": "Error",
+        "code": 2734
+    },
 
     "Import declaration '{0}' is using private name '{1}'.": {
         "category": "Error",
@@ -2912,7 +2940,7 @@
         "category": "Error",
         "code": 5070
     },
-    "Option '--resolveJsonModule' can only be specified when module code generation is 'commonjs'.": {
+    "Option '--resolveJsonModule' can only be specified when module code generation is 'commonjs', 'amd', 'es2015' or 'esNext'.": {
         "category": "Error",
         "code": 5071
     },
@@ -3294,7 +3322,7 @@
         "category": "Message",
         "code": 6104
     },
-    "Expected type of '{0}' field in 'package.json' to be 'string', got '{1}'.": {
+    "Expected type of '{0}' field in 'package.json' to be '{1}', got '{2}'.": {
         "category": "Message",
         "code": 6105
     },
@@ -3692,6 +3720,38 @@
         "category": "Error",
         "code": 6205
     },
+    "'package.json' has a 'typesVersions' field with version-specific path mappings.": {
+        "category": "Message",
+        "code": 6206
+    },
+    "'package.json' does not have a 'typesVersions' entry that matches version '{0}'.": {
+        "category": "Message",
+        "code": 6207
+    },
+    "'package.json' has a 'typesVersions' entry '{0}' that matches compiler version '{1}', looking for a pattern to match module name '{2}'.": {
+        "category": "Message",
+        "code": 6208
+    },
+    "'package.json' has a 'typesVersions' entry '{0}' that is not a valid semver range.": {
+        "category": "Message",
+        "code": 6209
+    },
+    "An argument for '{0}' was not provided.": {
+        "category": "Message",
+        "code": 6210
+    },
+    "An argument matching this binding pattern was not provided.": {
+        "category": "Message",
+        "code": 6211
+    },
+    "Did you mean to call this expression?": {
+        "category": "Message",
+        "code": 6212
+    },
+    "Did you mean to use `new` with this expression?": {
+        "category": "Message",
+        "code": 6213
+    },
 
     "Projects to reference": {
         "category": "Message",

src/compiler/diagnosticMessages.json

@@ -1780,7 +1780,9 @@ namespace ts {
 
         function emitExpressionStatement(node: ExpressionStatement) {
             emitExpression(node.expression);
-            if (!isJsonSourceFile(currentSourceFile)) {
+            // Emit semicolon in non json files
+            // or if json file that created synthesized expression(eg.define expression statement when --out and amd code generation)
+            if (!isJsonSourceFile(currentSourceFile) || nodeIsSynthesized(node.expression)) {
                 writeSemicolon();
             }
         }
@@ -2816,7 +2818,8 @@ namespace ts {
             const parameter = singleOrUndefined(parameters);
             return parameter
                 && parameter.pos === parentNode.pos // may not have parsed tokens between parent and parameter
-                && !(isArrowFunction(parentNode) && parentNode.type) // arrow function may not have return type annotation
+                && isArrowFunction(parentNode)      // only arrow functions may have simple arrow head
+                && !parentNode.type                 // arrow function may not have return type annotation
                 && !some(parentNode.decorators)     // parent may not have decorators
                 && !some(parentNode.modifiers)      // parent may not have modifiers
                 && !some(parentNode.typeParameters) // parent may not have type parameters