Add test

tests/baselines/reference/erasableSyntaxOnly.errors.txt

@@ -1,5 +1,6 @@
 commonjs.cts(1,1): error TS1294: This syntax is not allowed when 'erasableSyntaxOnly' is enabled.
 commonjs.cts(2,1): error TS1294: This syntax is not allowed when 'erasableSyntaxOnly' is enabled.
+esm.mts(2,1): error TS1294: This syntax is not allowed when 'erasableSyntaxOnly' is enabled.
 index.ts(3,17): error TS1294: This syntax is not allowed when 'erasableSyntaxOnly' is enabled.
 index.ts(6,11): error TS1294: This syntax is not allowed when 'erasableSyntaxOnly' is enabled.
 index.ts(10,11): error TS1294: This syntax is not allowed when 'erasableSyntaxOnly' is enabled.
@@ -104,4 +105,11 @@ index.ts(28,12): error TS1294: This syntax is not allowed when 'erasableSyntaxOn
 ==== other.d.cts (0 errors) ====
     declare function foo(): void;
     export = foo;
+
+
+==== esm.mts (1 errors) ====
+    const foo = 1234;
+    export default foo;
+    ~~~~~~~~~~~~~~~~~~~
+!!! error TS1294: This syntax is not allowed when 'erasableSyntaxOnly' is enabled.
 

tests/baselines/reference/erasableSyntaxOnly.js

@@ -74,6 +74,11 @@ export = foo;
 //// [other.d.cts]
 declare function foo(): void;
 export = foo;
+
+
+//// [esm.mts]
+const foo = 1234;
+export default foo;
 
 
 //// [index.js]
@@ -119,3 +124,6 @@ var MyClassOk = /** @class */ (function () {
 "use strict";
 var foo = require("./other.cjs");
 module.exports = foo;
+//// [esm.mjs]
+var foo = 1234;
+export default foo;

tests/baselines/reference/erasableSyntaxOnly.symbols

@@ -133,3 +133,11 @@ declare function foo(): void;
 export = foo;
 >foo : Symbol(foo, Decl(other.d.cts, 0, 0))
 
+
+=== esm.mts ===
+const foo = 1234;
+>foo : Symbol(foo, Decl(esm.mts, 0, 5))
+
+export default foo;
+>foo : Symbol(foo, Decl(esm.mts, 0, 5))
+

tests/baselines/reference/erasableSyntaxOnly.types

@@ -179,3 +179,15 @@ export = foo;
 >foo : () => void
 >    : ^^^^^^    
 
+
+=== esm.mts ===
+const foo = 1234;
+>foo : 1234
+>    : ^^^^
+>1234 : 1234
+>     : ^^^^
+
+export default foo;
+>foo : 1234
+>    : ^^^^
+

tests/baselines/reference/erasableSyntaxOnlyDeclaration.errors.txt

@@ -1,3 +1,4 @@
+esm.d.mts(1,1): error TS1046: Top-level declarations in .d.ts files must start with either a 'declare' or 'export' modifier.
 index.d.ts(1,1): error TS1046: Top-level declarations in .d.ts files must start with either a 'declare' or 'export' modifier.
 
 
@@ -65,4 +66,11 @@ index.d.ts(1,1): error TS1046: Top-level declarations in .d.ts files must start
 ==== other.d.cts (0 errors) ====
     declare function foo(): void;
     export = foo;
+
+
+==== esm.d.mts (1 errors) ====
+    const foo = 1234;
+    ~~~~~
+!!! error TS1046: Top-level declarations in .d.ts files must start with either a 'declare' or 'export' modifier.
+    export default foo;
 

tests/baselines/reference/erasableSyntaxOnlyDeclaration.symbols

@@ -112,3 +112,11 @@ declare function foo(): void;
 export = foo;
 >foo : Symbol(foo, Decl(other.d.cts, 0, 0))
 
+
+=== esm.d.mts ===
+const foo = 1234;
+>foo : Symbol(foo, Decl(esm.d.mts, 0, 5))
+
+export default foo;
+>foo : Symbol(foo, Decl(esm.d.mts, 0, 5))
+

tests/baselines/reference/erasableSyntaxOnlyDeclaration.types

@@ -154,3 +154,15 @@ export = foo;
 >foo : () => void
 >    : ^^^^^^    
 
+
+=== esm.d.mts ===
+const foo = 1234;
+>foo : 1234
+>    : ^^^^
+>1234 : 1234
+>     : ^^^^
+
+export default foo;
+>foo : 1234
+>    : ^^^^
+

tests/cases/compiler/erasableSyntaxOnly.ts

@@ -74,3 +74,8 @@ export = foo;
 // @filename: other.d.cts
 declare function foo(): void;
 export = foo;
+
+
+// @filename: esm.mts
+const foo = 1234;
+export default foo;

tests/cases/compiler/erasableSyntaxOnlyDeclaration.ts

@@ -66,3 +66,8 @@ export = foo;
 // @filename: other.d.cts
 declare function foo(): void;
 export = foo;
+
+
+// @filename: esm.d.mts
+const foo = 1234;
+export default foo;