Merge pull request #29167 from saschanaz/es2019

Add ES2019 target

Author: rbuckton

src/compiler/binder.ts

@@ -3296,7 +3296,7 @@ namespace ts {
         let transformFlags = subtreeFlags;
 
         if (!node.variableDeclaration) {
-            transformFlags |= TransformFlags.AssertESNext;
+            transformFlags |= TransformFlags.AssertES2019;
         }
         else if (isBindingPattern(node.variableDeclaration.name)) {
             transformFlags |= TransformFlags.AssertES2015;

src/compiler/commandLineParser.ts

@@ -15,6 +15,7 @@ namespace ts {
         ["es2016", "lib.es2016.d.ts"],
         ["es2017", "lib.es2017.d.ts"],
         ["es2018", "lib.es2018.d.ts"],
+        ["es2019", "lib.es2019.d.ts"],
         ["esnext", "lib.esnext.d.ts"],
         // Host only
         ["dom", "lib.dom.d.ts"],
@@ -42,8 +43,11 @@ namespace ts {
         ["es2018.intl", "lib.es2018.intl.d.ts"],
         ["es2018.promise", "lib.es2018.promise.d.ts"],
         ["es2018.regexp", "lib.es2018.regexp.d.ts"],
-        ["esnext.array", "lib.esnext.array.d.ts"],
-        ["esnext.symbol", "lib.esnext.symbol.d.ts"],
+        ["es2019.array", "lib.es2019.array.d.ts"],
+        ["es2019.string", "lib.es2019.string.d.ts"],
+        ["es2019.symbol", "lib.es2019.symbol.d.ts"],
+        ["esnext.array", "lib.es2019.array.d.ts"],
+        ["esnext.symbol", "lib.es2019.symbol.d.ts"],
         ["esnext.asynciterable", "lib.es2018.asynciterable.d.ts"],
         ["esnext.intl", "lib.esnext.intl.d.ts"],
         ["esnext.bigint", "lib.esnext.bigint.d.ts"]
@@ -198,14 +202,15 @@ namespace ts {
                 es2016: ScriptTarget.ES2016,
                 es2017: ScriptTarget.ES2017,
                 es2018: ScriptTarget.ES2018,
+                es2019: ScriptTarget.ES2019,
                 esnext: ScriptTarget.ESNext,
             }),
             affectsSourceFile: true,
             affectsModuleResolution: true,
             paramType: Diagnostics.VERSION,
             showInSimplifiedHelpView: true,
             category: Diagnostics.Basic_Options,
-            description: Diagnostics.Specify_ECMAScript_target_version_Colon_ES3_default_ES5_ES2015_ES2016_ES2017_ES2018_or_ESNEXT,
+            description: Diagnostics.Specify_ECMAScript_target_version_Colon_ES3_default_ES5_ES2015_ES2016_ES2017_ES2018_ES2019_or_ESNEXT,
         },
         {
             name: "module",

src/compiler/diagnosticMessages.json

@@ -3109,7 +3109,7 @@
         "category": "Message",
         "code": 6014
     },
-    "Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017','ES2018' or 'ESNEXT'.": {
+    "Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'.": {
         "category": "Message",
         "code": 6015
     },

src/compiler/transformer.ts

@@ -42,6 +42,10 @@ namespace ts {
             transformers.push(transformESNext);
         }
 
+        if (languageVersion < ScriptTarget.ES2019) {
+            transformers.push(transformES2019);
+        }
+
         if (languageVersion < ScriptTarget.ES2018) {
             transformers.push(transformES2018);
         }

src/compiler/transformers/es2019.ts

@@ -0,0 +1,37 @@
+/*@internal*/
+namespace ts {
+    export function transformES2019(context: TransformationContext) {
+        return chainBundle(transformSourceFile);
+
+        function transformSourceFile(node: SourceFile) {
+            if (node.isDeclarationFile) {
+                return node;
+            }
+
+            return visitEachChild(node, visitor, context);
+        }
+
+        function visitor(node: Node): VisitResult<Node> {
+            if ((node.transformFlags & TransformFlags.ContainsES2019) === 0) {
+                return node;
+            }
+            switch (node.kind) {
+                case SyntaxKind.CatchClause:
+                    return visitCatchClause(node as CatchClause);
+                default:
+                    return visitEachChild(node, visitor, context);
+            }
+        }
+
+        function visitCatchClause(node: CatchClause): CatchClause {
+            if (!node.variableDeclaration) {
+                return updateCatchClause(
+                    node,
+                    createVariableDeclaration(createTempVariable(/*recordTempVariable*/ undefined)),
+                    visitNode(node.block, visitor, isBlock)
+                );
+            }
+            return visitEachChild(node, visitor, context);
+        }
+    }
+}

src/compiler/transformers/esnext.ts

@@ -16,22 +16,9 @@ namespace ts {
                 return node;
             }
             switch (node.kind) {
-                case SyntaxKind.CatchClause:
-                    return visitCatchClause(node as CatchClause);
                 default:
                     return visitEachChild(node, visitor, context);
             }
         }
-
-        function visitCatchClause(node: CatchClause): CatchClause {
-            if (!node.variableDeclaration) {
-                return updateCatchClause(
-                    node,
-                    createVariableDeclaration(createTempVariable(/*recordTempVariable*/ undefined)),
-                    visitNode(node.block, visitor, isBlock)
-                );
-            }
-            return visitEachChild(node, visitor, context);
-        }
     }
 }

src/compiler/tsconfig.json

@@ -31,6 +31,7 @@
         "transformers/ts.ts",
         "transformers/es2017.ts",
         "transformers/es2018.ts",
+        "transformers/es2019.ts",
         "transformers/esnext.ts",
         "transformers/jsx.ts",
         "transformers/es2016.ts",

src/compiler/types.ts

@@ -4658,7 +4658,8 @@ namespace ts {
         ES2016 = 3,
         ES2017 = 4,
         ES2018 = 5,
-        ESNext = 6,
+        ES2019 = 6,
+        ESNext = 7,
         JSON = 100,
         Latest = ESNext,
     }
@@ -5072,6 +5073,7 @@ namespace ts {
         Super = 1 << 25,
         ContainsSuper = 1 << 26,
         ContainsES2018 = 1 << 27,
+        ContainsES2019 = 1 << 28,
 
         // Please leave this as 1 << 29.
         // It is the maximum bit we can set before we outgrow the size of a v8 small integer (SMI) on an x86 system.
@@ -5083,6 +5085,7 @@ namespace ts {
         AssertTypeScript = TypeScript | ContainsTypeScript,
         AssertJsx = ContainsJsx,
         AssertESNext = ContainsESNext,
+        AssertES2019 = ContainsES2019,
         AssertES2018 = ContainsES2018,
         AssertES2017 = ContainsES2017,
         AssertES2016 = ContainsES2016,

src/compiler/utilities.ts

@@ -4603,6 +4603,8 @@ namespace ts {
         switch (options.target) {
             case ScriptTarget.ESNext:
                 return "lib.esnext.full.d.ts";
+            case ScriptTarget.ES2019:
+                return "lib.es2019.full.d.ts";
             case ScriptTarget.ES2018:
                 return "lib.es2018.full.d.ts";
             case ScriptTarget.ES2017: