From ee1d08ef65a9f19b31c7c66e8b9e6b13f2dd6c78 Mon Sep 17 00:00:00 2001
From: Noj Vek <noj.vek@mixpanel.com>
Date: Sun, 21 Jan 2018 10:04:20 -0800
Subject: [PATCH 1/6] Add emitOnlyDeclarations flag

---
 src/compiler/commandLineParser.ts    |  6 ++++++
 src/compiler/diagnosticMessages.json |  4 ++++
 src/compiler/program.ts              |  8 +++++++-
 src/compiler/types.ts                |  1 +
 src/harness/harness.ts               | 12 +++++++++---
 5 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/src/compiler/commandLineParser.ts b/src/compiler/commandLineParser.ts
index eb9f1e3cf34a6..831f8aac8a3bc 100644
--- a/src/compiler/commandLineParser.ts
+++ b/src/compiler/commandLineParser.ts
@@ -186,6 +186,12 @@ namespace ts {
             category: Diagnostics.Basic_Options,
             description: Diagnostics.Generates_corresponding_d_ts_file,
         },
+        {
+            name: "emitOnlyDeclarations",
+            type: "boolean",
+            category: Diagnostics.Advanced_Options,
+            description: Diagnostics.Only_emit_declaration_files,
+        },
         {
             name: "sourceMap",
             type: "boolean",
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index 7a62d6d5aa4a1..0ee40ff763c80 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -2807,6 +2807,10 @@
         "category": "Message",
         "code": 6013
     },
+    "Only emit declaration files.": {
+        "category": "Message",
+        "code": 6014
+    },
     "Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017','ES2018' or 'ESNEXT'.": {
         "category": "Message",
         "code": 6015
diff --git a/src/compiler/program.ts b/src/compiler/program.ts
index bd45857fc51dc..e11c3547921ce 100755
--- a/src/compiler/program.ts
+++ b/src/compiler/program.ts
@@ -2201,6 +2201,10 @@ namespace ts {
                 programDiagnostics.add(createCompilerDiagnostic(Diagnostics.Option_0_cannot_be_specified_without_specifying_option_1, "checkJs", "allowJs"));
             }
 
+            if (options.noEmit && options.emitDeclarationsOnly) {
+                createDiagnosticForOptionName(Diagnostics.Option_0_cannot_be_specified_with_option_1, "noEmit", "emitDeclarationsOnly");
+            }
+
             if (options.emitDecoratorMetadata &&
                 !options.experimentalDecorators) {
                 createDiagnosticForOptionName(Diagnostics.Option_0_cannot_be_specified_without_specifying_option_1, "emitDecoratorMetadata", "experimentalDecorators");
@@ -2223,7 +2227,9 @@ namespace ts {
                 const emitHost = getEmitHost();
                 const emitFilesSeen = createMap<true>();
                 forEachEmittedFile(emitHost, (emitFileNames) => {
-                    verifyEmitFilePath(emitFileNames.jsFilePath, emitFilesSeen);
+                    if (!options.emitDeclarationsOnly) {
+                        verifyEmitFilePath(emitFileNames.jsFilePath, emitFilesSeen);
+                    }
                     verifyEmitFilePath(emitFileNames.declarationFilePath, emitFilesSeen);
                 });
             }
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index f6ca2f45d3401..481b91c9276e1 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -3967,6 +3967,7 @@ namespace ts {
         /** configFile is set as non enumerable property so as to avoid checking of json source files */
         /* @internal */ readonly configFile?: JsonSourceFile;
         declaration?: boolean;
+        emitDeclarationsOnly?: boolean;
         declarationDir?: string;
         /* @internal */ diagnostics?: boolean;
         /* @internal */ extendedDiagnostics?: boolean;
diff --git a/src/harness/harness.ts b/src/harness/harness.ts
index f2f8587d83412..1e5e619fe3202 100644
--- a/src/harness/harness.ts
+++ b/src/harness/harness.ts
@@ -1252,8 +1252,14 @@ namespace Harness {
             options: ts.CompilerOptions,
             // Current directory is needed for rwcRunner to be able to use currentDirectory defined in json file
             currentDirectory: string): DeclarationCompilationContext | undefined {
-            if (options.declaration && result.errors.length === 0 && result.declFilesCode.length !== result.files.length) {
-                throw new Error("There were no errors and declFiles generated did not match number of js files generated");
+
+            if (result.errors.length === 0) {
+                if (options.declaration && result.declFilesCode.length !== result.files.length) {
+                    throw new Error("There were no errors and declFiles generated did not match number of js files generated");
+                }
+                if (options.emitDeclarationsOnly && result.files.length > 0) {
+                    throw new Error("Only declaration files should be generated when emitOnlyDeclarations:true");
+                }
             }
 
             const declInputFiles: TestFile[] = [];
@@ -1654,7 +1660,7 @@ namespace Harness {
         }
 
         export function doJsEmitBaseline(baselinePath: string, header: string, options: ts.CompilerOptions, result: CompilerResult, tsConfigFiles: Harness.Compiler.TestFile[], toBeCompiled: Harness.Compiler.TestFile[], otherFiles: Harness.Compiler.TestFile[], harnessSettings: Harness.TestCaseParser.CompilerSettings) {
-            if (!options.noEmit && result.files.length === 0 && result.errors.length === 0) {
+            if (!options.noEmit && !options.noEmitJs && result.files.length === 0 && result.errors.length === 0) {
                 throw new Error("Expected at least one js file to be emitted or at least one error to be created.");
             }
 

From 7aa27b8dd724579e94efad5518166f4a7c0a8613 Mon Sep 17 00:00:00 2001
From: Noj Vek <noj.vek@mixpanel.com>
Date: Sun, 21 Jan 2018 10:30:48 -0800
Subject: [PATCH 2/6] Fix name

---
 src/compiler/commandLineParser.ts    | 6 +++---
 src/compiler/diagnosticMessages.json | 2 +-
 src/harness/harness.ts               | 2 +-
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/compiler/commandLineParser.ts b/src/compiler/commandLineParser.ts
index 831f8aac8a3bc..07cd342d43ec4 100644
--- a/src/compiler/commandLineParser.ts
+++ b/src/compiler/commandLineParser.ts
@@ -187,10 +187,10 @@ namespace ts {
             description: Diagnostics.Generates_corresponding_d_ts_file,
         },
         {
-            name: "emitOnlyDeclarations",
+            name: "emitDeclarationsOnly",
             type: "boolean",
-            category: Diagnostics.Advanced_Options,
-            description: Diagnostics.Only_emit_declaration_files,
+            category: Diagnostics.Experimental_Options,
+            description: Diagnostics.Only_emit_d_ts_declaration_files,
         },
         {
             name: "sourceMap",
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index 0ee40ff763c80..6fffd576e7caf 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -2807,7 +2807,7 @@
         "category": "Message",
         "code": 6013
     },
-    "Only emit declaration files.": {
+    "Only emit '.d.ts' declaration files.": {
         "category": "Message",
         "code": 6014
     },
diff --git a/src/harness/harness.ts b/src/harness/harness.ts
index 1e5e619fe3202..9e070d6e9410c 100644
--- a/src/harness/harness.ts
+++ b/src/harness/harness.ts
@@ -1258,7 +1258,7 @@ namespace Harness {
                     throw new Error("There were no errors and declFiles generated did not match number of js files generated");
                 }
                 if (options.emitDeclarationsOnly && result.files.length > 0) {
-                    throw new Error("Only declaration files should be generated when emitOnlyDeclarations:true");
+                    throw new Error("Only declaration files should be generated when emitDeclarationsOnly:true");
                 }
             }
 

From 6a41628a906288b09c8c6e12bf383baab74b2599 Mon Sep 17 00:00:00 2001
From: Noj Vek <noj.vek@mixpanel.com>
Date: Sun, 21 Jan 2018 14:15:45 -0800
Subject: [PATCH 3/6] verifyOptions checking logic

---
 src/compiler/emitter.ts |  2 +-
 src/compiler/program.ts | 10 ++++++++--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 6f3041666bab1..03ff63a421123 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -135,7 +135,7 @@ namespace ts {
 
         function emitSourceFileOrBundle({ jsFilePath, sourceMapFilePath, declarationFilePath }: EmitFileNames, sourceFileOrBundle: SourceFile | Bundle) {
             // Make sure not to write js file and source map file if any of them cannot be written
-            if (!host.isEmitBlocked(jsFilePath) && !compilerOptions.noEmit) {
+            if (!host.isEmitBlocked(jsFilePath) && !compilerOptions.noEmit && !compilerOptions.emitDeclarationsOnly) {
                 if (!emitOnlyDtsFiles) {
                     printSourceFileOrBundle(jsFilePath, sourceMapFilePath, sourceFileOrBundle);
                 }
diff --git a/src/compiler/program.ts b/src/compiler/program.ts
index e11c3547921ce..23f9b08aa798c 100755
--- a/src/compiler/program.ts
+++ b/src/compiler/program.ts
@@ -2201,8 +2201,14 @@ namespace ts {
                 programDiagnostics.add(createCompilerDiagnostic(Diagnostics.Option_0_cannot_be_specified_without_specifying_option_1, "checkJs", "allowJs"));
             }
 
-            if (options.noEmit && options.emitDeclarationsOnly) {
-                createDiagnosticForOptionName(Diagnostics.Option_0_cannot_be_specified_with_option_1, "noEmit", "emitDeclarationsOnly");
+            if (options.emitDeclarationsOnly) {
+                if (!options.declaration) {
+                    createDiagnosticForOptionName(Diagnostics.Option_0_cannot_be_specified_without_specifying_option_1, "emitDeclarationsOnly", "declarations");
+                }
+
+                if (options.noEmit) {
+                    createDiagnosticForOptionName(Diagnostics.Option_0_cannot_be_specified_with_option_1, "emitDeclarationsOnly", "noEmit");
+                }
             }
 
             if (options.emitDecoratorMetadata &&

From fdcb8f48aba13f5384ab32881a8e881804d87b3e Mon Sep 17 00:00:00 2001
From: Noj Vek <noj.vek@mixpanel.com>
Date: Sun, 21 Jan 2018 14:29:50 -0800
Subject: [PATCH 4/6] Passing tests

---
 src/compiler/commandLineParser.ts                  | 2 +-
 tests/baselines/reference/api/tsserverlibrary.d.ts | 1 +
 tests/baselines/reference/api/typescript.d.ts      | 1 +
 3 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/compiler/commandLineParser.ts b/src/compiler/commandLineParser.ts
index 07cd342d43ec4..9c30cb87a4daa 100644
--- a/src/compiler/commandLineParser.ts
+++ b/src/compiler/commandLineParser.ts
@@ -189,7 +189,7 @@ namespace ts {
         {
             name: "emitDeclarationsOnly",
             type: "boolean",
-            category: Diagnostics.Experimental_Options,
+            category: Diagnostics.Advanced_Options,
             description: Diagnostics.Only_emit_d_ts_declaration_files,
         },
         {
diff --git a/tests/baselines/reference/api/tsserverlibrary.d.ts b/tests/baselines/reference/api/tsserverlibrary.d.ts
index cd1b577b71173..3db774c736f01 100644
--- a/tests/baselines/reference/api/tsserverlibrary.d.ts
+++ b/tests/baselines/reference/api/tsserverlibrary.d.ts
@@ -2266,6 +2266,7 @@ declare namespace ts {
         charset?: string;
         checkJs?: boolean;
         declaration?: boolean;
+        emitDeclarationsOnly?: boolean;
         declarationDir?: string;
         disableSizeLimit?: boolean;
         downlevelIteration?: boolean;
diff --git a/tests/baselines/reference/api/typescript.d.ts b/tests/baselines/reference/api/typescript.d.ts
index 3cbca96f8fa97..41dde69a87f83 100644
--- a/tests/baselines/reference/api/typescript.d.ts
+++ b/tests/baselines/reference/api/typescript.d.ts
@@ -2266,6 +2266,7 @@ declare namespace ts {
         charset?: string;
         checkJs?: boolean;
         declaration?: boolean;
+        emitDeclarationsOnly?: boolean;
         declarationDir?: string;
         disableSizeLimit?: boolean;
         downlevelIteration?: boolean;

From e9b6c990181ae9dd8d39896ae71dac8debab0d7b Mon Sep 17 00:00:00 2001
From: Noj Vek <noj.vek@mixpanel.com>
Date: Sun, 21 Jan 2018 14:35:04 -0800
Subject: [PATCH 5/6] doJsEmitBaseline

---
 src/harness/harness.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/harness/harness.ts b/src/harness/harness.ts
index 9e070d6e9410c..9ec5ad2f4d108 100644
--- a/src/harness/harness.ts
+++ b/src/harness/harness.ts
@@ -1660,7 +1660,7 @@ namespace Harness {
         }
 
         export function doJsEmitBaseline(baselinePath: string, header: string, options: ts.CompilerOptions, result: CompilerResult, tsConfigFiles: Harness.Compiler.TestFile[], toBeCompiled: Harness.Compiler.TestFile[], otherFiles: Harness.Compiler.TestFile[], harnessSettings: Harness.TestCaseParser.CompilerSettings) {
-            if (!options.noEmit && !options.noEmitJs && result.files.length === 0 && result.errors.length === 0) {
+            if (!options.noEmit && !options.emitDeclarationsOnly && result.files.length === 0 && result.errors.length === 0) {
                 throw new Error("Expected at least one js file to be emitted or at least one error to be created.");
             }
 

From e34b4fbad7f4b137d15adf9035ff9b48dadb5bf3 Mon Sep 17 00:00:00 2001
From: Noj Vek <noj.vek@mixpanel.com>
Date: Mon, 22 Jan 2018 22:35:53 -0800
Subject: [PATCH 6/6] Tests !!!

---
 src/harness/harness.ts                        | 14 +++++---
 .../reference/declFileEmitDeclarationsOnly.js | 26 +++++++++++++++
 .../declFileEmitDeclarationsOnly.symbols      | 29 +++++++++++++++++
 .../declFileEmitDeclarationsOnly.types        | 32 +++++++++++++++++++
 ...lFileEmitDeclarationsOnlyError1.errors.txt |  7 ++++
 ...declFileEmitDeclarationsOnlyError1.symbols |  4 +++
 .../declFileEmitDeclarationsOnlyError1.types  |  5 +++
 ...lFileEmitDeclarationsOnlyError2.errors.txt |  9 ++++++
 ...declFileEmitDeclarationsOnlyError2.symbols |  4 +++
 .../declFileEmitDeclarationsOnlyError2.types  |  5 +++
 .../compiler/declFileEmitDeclarationsOnly.ts  | 16 ++++++++++
 .../declFileEmitDeclarationsOnlyError1.ts     |  4 +++
 .../declFileEmitDeclarationsOnlyError2.ts     |  5 +++
 13 files changed, 155 insertions(+), 5 deletions(-)
 create mode 100644 tests/baselines/reference/declFileEmitDeclarationsOnly.js
 create mode 100644 tests/baselines/reference/declFileEmitDeclarationsOnly.symbols
 create mode 100644 tests/baselines/reference/declFileEmitDeclarationsOnly.types
 create mode 100644 tests/baselines/reference/declFileEmitDeclarationsOnlyError1.errors.txt
 create mode 100644 tests/baselines/reference/declFileEmitDeclarationsOnlyError1.symbols
 create mode 100644 tests/baselines/reference/declFileEmitDeclarationsOnlyError1.types
 create mode 100644 tests/baselines/reference/declFileEmitDeclarationsOnlyError2.errors.txt
 create mode 100644 tests/baselines/reference/declFileEmitDeclarationsOnlyError2.symbols
 create mode 100644 tests/baselines/reference/declFileEmitDeclarationsOnlyError2.types
 create mode 100644 tests/cases/compiler/declFileEmitDeclarationsOnly.ts
 create mode 100644 tests/cases/compiler/declFileEmitDeclarationsOnlyError1.ts
 create mode 100644 tests/cases/compiler/declFileEmitDeclarationsOnlyError2.ts

diff --git a/src/harness/harness.ts b/src/harness/harness.ts
index 9ec5ad2f4d108..3e6f4cfa16390 100644
--- a/src/harness/harness.ts
+++ b/src/harness/harness.ts
@@ -1254,11 +1254,15 @@ namespace Harness {
             currentDirectory: string): DeclarationCompilationContext | undefined {
 
             if (result.errors.length === 0) {
-                if (options.declaration && result.declFilesCode.length !== result.files.length) {
-                    throw new Error("There were no errors and declFiles generated did not match number of js files generated");
-                }
-                if (options.emitDeclarationsOnly && result.files.length > 0) {
-                    throw new Error("Only declaration files should be generated when emitDeclarationsOnly:true");
+                if (options.declaration) {
+                    if (options.emitDeclarationsOnly) {
+                        if (result.files.length > 0 || result.declFilesCode.length === 0) {
+                            throw new Error("Only declaration files should be generated when emitDeclarationsOnly:true");
+                        }
+                    }
+                    else if (result.declFilesCode.length !== result.files.length) {
+                        throw new Error("There were no errors and declFiles generated did not match number of js files generated");
+                    }
                 }
             }
 
diff --git a/tests/baselines/reference/declFileEmitDeclarationsOnly.js b/tests/baselines/reference/declFileEmitDeclarationsOnly.js
new file mode 100644
index 0000000000000..78d9842fe88b6
--- /dev/null
+++ b/tests/baselines/reference/declFileEmitDeclarationsOnly.js
@@ -0,0 +1,26 @@
+//// [helloworld.ts]
+const Log = {
+  info(msg: string) {}
+}
+
+class HelloWorld {
+  constructor(private name: string) {
+  }
+
+  public hello() {
+    Log.info(`Hello ${this.name}`);
+  }
+}
+
+
+
+
+//// [helloworld.d.ts]
+declare const Log: {
+    info(msg: string): void;
+};
+declare class HelloWorld {
+    private name;
+    constructor(name: string);
+    hello(): void;
+}
diff --git a/tests/baselines/reference/declFileEmitDeclarationsOnly.symbols b/tests/baselines/reference/declFileEmitDeclarationsOnly.symbols
new file mode 100644
index 0000000000000..e2a277fb60347
--- /dev/null
+++ b/tests/baselines/reference/declFileEmitDeclarationsOnly.symbols
@@ -0,0 +1,29 @@
+=== tests/cases/compiler/helloworld.ts ===
+const Log = {
+>Log : Symbol(Log, Decl(helloworld.ts, 0, 5))
+
+  info(msg: string) {}
+>info : Symbol(info, Decl(helloworld.ts, 0, 13))
+>msg : Symbol(msg, Decl(helloworld.ts, 1, 7))
+}
+
+class HelloWorld {
+>HelloWorld : Symbol(HelloWorld, Decl(helloworld.ts, 2, 1))
+
+  constructor(private name: string) {
+>name : Symbol(HelloWorld.name, Decl(helloworld.ts, 5, 14))
+  }
+
+  public hello() {
+>hello : Symbol(HelloWorld.hello, Decl(helloworld.ts, 6, 3))
+
+    Log.info(`Hello ${this.name}`);
+>Log.info : Symbol(info, Decl(helloworld.ts, 0, 13))
+>Log : Symbol(Log, Decl(helloworld.ts, 0, 5))
+>info : Symbol(info, Decl(helloworld.ts, 0, 13))
+>this.name : Symbol(HelloWorld.name, Decl(helloworld.ts, 5, 14))
+>this : Symbol(HelloWorld, Decl(helloworld.ts, 2, 1))
+>name : Symbol(HelloWorld.name, Decl(helloworld.ts, 5, 14))
+  }
+}
+
diff --git a/tests/baselines/reference/declFileEmitDeclarationsOnly.types b/tests/baselines/reference/declFileEmitDeclarationsOnly.types
new file mode 100644
index 0000000000000..9a3cf8cfc70b0
--- /dev/null
+++ b/tests/baselines/reference/declFileEmitDeclarationsOnly.types
@@ -0,0 +1,32 @@
+=== tests/cases/compiler/helloworld.ts ===
+const Log = {
+>Log : { info(msg: string): void; }
+>{  info(msg: string) {}} : { info(msg: string): void; }
+
+  info(msg: string) {}
+>info : (msg: string) => void
+>msg : string
+}
+
+class HelloWorld {
+>HelloWorld : HelloWorld
+
+  constructor(private name: string) {
+>name : string
+  }
+
+  public hello() {
+>hello : () => void
+
+    Log.info(`Hello ${this.name}`);
+>Log.info(`Hello ${this.name}`) : void
+>Log.info : (msg: string) => void
+>Log : { info(msg: string): void; }
+>info : (msg: string) => void
+>`Hello ${this.name}` : string
+>this.name : string
+>this : this
+>name : string
+  }
+}
+
diff --git a/tests/baselines/reference/declFileEmitDeclarationsOnlyError1.errors.txt b/tests/baselines/reference/declFileEmitDeclarationsOnlyError1.errors.txt
new file mode 100644
index 0000000000000..88a154cc508fb
--- /dev/null
+++ b/tests/baselines/reference/declFileEmitDeclarationsOnlyError1.errors.txt
@@ -0,0 +1,7 @@
+error TS5052: Option 'emitDeclarationsOnly' cannot be specified without specifying option 'declarations'.
+
+
+!!! error TS5052: Option 'emitDeclarationsOnly' cannot be specified without specifying option 'declarations'.
+==== tests/cases/compiler/hello.ts (0 errors) ====
+    var hello = "yo!";
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/declFileEmitDeclarationsOnlyError1.symbols b/tests/baselines/reference/declFileEmitDeclarationsOnlyError1.symbols
new file mode 100644
index 0000000000000..52b2f9bbe64a4
--- /dev/null
+++ b/tests/baselines/reference/declFileEmitDeclarationsOnlyError1.symbols
@@ -0,0 +1,4 @@
+=== tests/cases/compiler/hello.ts ===
+var hello = "yo!";
+>hello : Symbol(hello, Decl(hello.ts, 0, 3))
+
diff --git a/tests/baselines/reference/declFileEmitDeclarationsOnlyError1.types b/tests/baselines/reference/declFileEmitDeclarationsOnlyError1.types
new file mode 100644
index 0000000000000..e1603394d7c97
--- /dev/null
+++ b/tests/baselines/reference/declFileEmitDeclarationsOnlyError1.types
@@ -0,0 +1,5 @@
+=== tests/cases/compiler/hello.ts ===
+var hello = "yo!";
+>hello : string
+>"yo!" : "yo!"
+
diff --git a/tests/baselines/reference/declFileEmitDeclarationsOnlyError2.errors.txt b/tests/baselines/reference/declFileEmitDeclarationsOnlyError2.errors.txt
new file mode 100644
index 0000000000000..7c067d83ba221
--- /dev/null
+++ b/tests/baselines/reference/declFileEmitDeclarationsOnlyError2.errors.txt
@@ -0,0 +1,9 @@
+error TS5052: Option 'emitDeclarationsOnly' cannot be specified without specifying option 'declarations'.
+error TS5053: Option 'emitDeclarationsOnly' cannot be specified with option 'noEmit'.
+
+
+!!! error TS5052: Option 'emitDeclarationsOnly' cannot be specified without specifying option 'declarations'.
+!!! error TS5053: Option 'emitDeclarationsOnly' cannot be specified with option 'noEmit'.
+==== tests/cases/compiler/hello.ts (0 errors) ====
+    var hello = "yo!";
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/declFileEmitDeclarationsOnlyError2.symbols b/tests/baselines/reference/declFileEmitDeclarationsOnlyError2.symbols
new file mode 100644
index 0000000000000..52b2f9bbe64a4
--- /dev/null
+++ b/tests/baselines/reference/declFileEmitDeclarationsOnlyError2.symbols
@@ -0,0 +1,4 @@
+=== tests/cases/compiler/hello.ts ===
+var hello = "yo!";
+>hello : Symbol(hello, Decl(hello.ts, 0, 3))
+
diff --git a/tests/baselines/reference/declFileEmitDeclarationsOnlyError2.types b/tests/baselines/reference/declFileEmitDeclarationsOnlyError2.types
new file mode 100644
index 0000000000000..e1603394d7c97
--- /dev/null
+++ b/tests/baselines/reference/declFileEmitDeclarationsOnlyError2.types
@@ -0,0 +1,5 @@
+=== tests/cases/compiler/hello.ts ===
+var hello = "yo!";
+>hello : string
+>"yo!" : "yo!"
+
diff --git a/tests/cases/compiler/declFileEmitDeclarationsOnly.ts b/tests/cases/compiler/declFileEmitDeclarationsOnly.ts
new file mode 100644
index 0000000000000..e55496e4ca368
--- /dev/null
+++ b/tests/cases/compiler/declFileEmitDeclarationsOnly.ts
@@ -0,0 +1,16 @@
+// @declaration: true
+// @emitDeclarationsOnly: true
+
+// @filename: helloworld.ts
+const Log = {
+  info(msg: string) {}
+}
+
+class HelloWorld {
+  constructor(private name: string) {
+  }
+
+  public hello() {
+    Log.info(`Hello ${this.name}`);
+  }
+}
diff --git a/tests/cases/compiler/declFileEmitDeclarationsOnlyError1.ts b/tests/cases/compiler/declFileEmitDeclarationsOnlyError1.ts
new file mode 100644
index 0000000000000..477934a7b2a61
--- /dev/null
+++ b/tests/cases/compiler/declFileEmitDeclarationsOnlyError1.ts
@@ -0,0 +1,4 @@
+// @emitDeclarationsOnly: true
+
+// @filename: hello.ts
+var hello = "yo!";
diff --git a/tests/cases/compiler/declFileEmitDeclarationsOnlyError2.ts b/tests/cases/compiler/declFileEmitDeclarationsOnlyError2.ts
new file mode 100644
index 0000000000000..994a6a5dbd867
--- /dev/null
+++ b/tests/cases/compiler/declFileEmitDeclarationsOnlyError2.ts
@@ -0,0 +1,5 @@
+// @noEmit: true
+// @emitDeclarationsOnly: true
+
+// @filename: hello.ts
+var hello = "yo!";