diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index 5b57556af00..6cb5858f8ee 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -2060,11 +2060,11 @@
         "category": "Error",
         "code": 5054
     },
-    "Cannot write file '{0}' which is one of the input files.": {
+    "Cannot write file '{0}' because it would overwrite input file.": {
         "category": "Error",
         "code": 5055
     },
-    "Cannot write file '{0}' since one or more input files would emit into it.": {
+    "Cannot write file '{0}' because it would be overwritten by multiple input files.": {
         "category": "Error",
         "code": 5056
     },
diff --git a/src/compiler/program.ts b/src/compiler/program.ts
index a029a481d19..0fab35dacb3 100644
--- a/src/compiler/program.ts
+++ b/src/compiler/program.ts
@@ -1289,20 +1289,20 @@ namespace ts {
                 forEachKey(emitFilesSeen, emitFilePath => {
                     // Report error if the output overwrites input file
                     if (hasFile(files, emitFilePath)) {
-                        createEmitBlockingDiagnostics(emitFilePath, Diagnostics.Cannot_write_file_0_which_is_one_of_the_input_files);
+                        createEmitBlockingDiagnostics(emitFilePath, Diagnostics.Cannot_write_file_0_because_it_would_overwrite_input_file);
                     }
 
                     // Report error if multiple files write into same file (except if specified by --out or --outFile)
                     if (emitFilePath !== (options.outFile || options.out)) {
                         // Not --out or --outFile emit, There should be single file emitting to this file
                         if (emitFilesSeen[emitFilePath].length > 1) {
-                            createEmitBlockingDiagnostics(emitFilePath, Diagnostics.Cannot_write_file_0_since_one_or_more_input_files_would_emit_into_it);
+                            createEmitBlockingDiagnostics(emitFilePath, Diagnostics.Cannot_write_file_0_because_it_would_be_overwritten_by_multiple_input_files);
                         }
                     }
                     else {
                         // --out or --outFile, error if there exist file emitting to single file colliding with --out
                         if (forEach(emitFilesSeen[emitFilePath], sourceFile => shouldEmitToOwnFile(sourceFile, options))) {
-                            createEmitBlockingDiagnostics(emitFilePath, Diagnostics.Cannot_write_file_0_since_one_or_more_input_files_would_emit_into_it);
+                            createEmitBlockingDiagnostics(emitFilePath, Diagnostics.Cannot_write_file_0_because_it_would_be_overwritten_by_multiple_input_files);
                         }
                     }
                 });
diff --git a/tests/baselines/reference/compileOnSaveWorksWhenEmitBlockingErrorOnOtherFile.baseline b/tests/baselines/reference/compileOnSaveWorksWhenEmitBlockingErrorOnOtherFile.baseline
index 5db889dc01d..f9bcca268ec 100644
--- a/tests/baselines/reference/compileOnSaveWorksWhenEmitBlockingErrorOnOtherFile.baseline
+++ b/tests/baselines/reference/compileOnSaveWorksWhenEmitBlockingErrorOnOtherFile.baseline
@@ -1,6 +1,6 @@
 EmitSkipped: true
 Diagnostics:
-  Cannot write file 'tests/cases/fourslash/b.js' which is one of the input files.
+  Cannot write file 'tests/cases/fourslash/b.js' because it would overwrite input file.
 
 EmitSkipped: false
 FileName : tests/cases/fourslash/a.js
diff --git a/tests/baselines/reference/declarationFileOverwriteError.errors.txt b/tests/baselines/reference/declarationFileOverwriteError.errors.txt
index fbf4948c203..a12c60482e9 100644
--- a/tests/baselines/reference/declarationFileOverwriteError.errors.txt
+++ b/tests/baselines/reference/declarationFileOverwriteError.errors.txt
@@ -1,7 +1,7 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.d.ts' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.d.ts' because it would overwrite input file.
 
 
-!!! error TS5055: Cannot write file 'a.d.ts' which is one of the input files.
+!!! error TS5055: Cannot write file 'a.d.ts' because it would overwrite input file.
 ==== tests/cases/compiler/a.d.ts (0 errors) ====
     
     declare class c {
diff --git a/tests/baselines/reference/declarationFileOverwriteErrorWithOut.errors.txt b/tests/baselines/reference/declarationFileOverwriteErrorWithOut.errors.txt
index b90bccbaf94..02251900345 100644
--- a/tests/baselines/reference/declarationFileOverwriteErrorWithOut.errors.txt
+++ b/tests/baselines/reference/declarationFileOverwriteErrorWithOut.errors.txt
@@ -1,7 +1,7 @@
-error TS5055: Cannot write file 'tests/cases/compiler/out.d.ts' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/out.d.ts' because it would overwrite input file.
 
 
-!!! error TS5055: Cannot write file 'out.d.ts' which is one of the input files.
+!!! error TS5055: Cannot write file 'out.d.ts' because it would overwrite input file.
 ==== tests/cases/compiler/out.d.ts (0 errors) ====
     
     declare class c {
diff --git a/tests/baselines/reference/filesEmittingIntoSameOutput.errors.txt b/tests/baselines/reference/filesEmittingIntoSameOutput.errors.txt
index 3a4c7eaad45..013a1445b0d 100644
--- a/tests/baselines/reference/filesEmittingIntoSameOutput.errors.txt
+++ b/tests/baselines/reference/filesEmittingIntoSameOutput.errors.txt
@@ -1,7 +1,7 @@
-error TS5056: Cannot write file 'tests/cases/compiler/a.js' since one or more input files would emit into it.
+error TS5056: Cannot write file 'tests/cases/compiler/a.js' because it would be overwritten by multiple input files.
 
 
-!!! error TS5056: Cannot write file 'tests/cases/compiler/a.js' since one or more input files would emit into it.
+!!! error TS5056: Cannot write file 'tests/cases/compiler/a.js' because it would be overwritten by multiple input files.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/filesEmittingIntoSameOutputWithOutOption.errors.txt b/tests/baselines/reference/filesEmittingIntoSameOutputWithOutOption.errors.txt
index 77cd91b9a7f..087a159a9bf 100644
--- a/tests/baselines/reference/filesEmittingIntoSameOutputWithOutOption.errors.txt
+++ b/tests/baselines/reference/filesEmittingIntoSameOutputWithOutOption.errors.txt
@@ -1,7 +1,7 @@
-error TS5056: Cannot write file 'tests/cases/compiler/a.js' since one or more input files would emit into it.
+error TS5056: Cannot write file 'tests/cases/compiler/a.js' because it would be overwritten by multiple input files.
 
 
-!!! error TS5056: Cannot write file 'tests/cases/compiler/a.js' since one or more input files would emit into it.
+!!! error TS5056: Cannot write file 'tests/cases/compiler/a.js' because it would be overwritten by multiple input files.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     export class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationAmbientVarDeclarationSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationAmbientVarDeclarationSyntax.errors.txt
index b0732afea72..19bfd5d1c02 100644
--- a/tests/baselines/reference/jsFileCompilationAmbientVarDeclarationSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationAmbientVarDeclarationSyntax.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,1): error TS8009: 'declare' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     declare var v;
     ~~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationDecoratorSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationDecoratorSyntax.errors.txt
index b7fec2eefc6..a39d2e1665c 100644
--- a/tests/baselines/reference/jsFileCompilationDecoratorSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationDecoratorSyntax.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,1): error TS8017: 'decorators' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     @internal class C { }
     ~~~~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationEmitBlockedCorrectly.errors.txt b/tests/baselines/reference/jsFileCompilationEmitBlockedCorrectly.errors.txt
index 5861e73f49b..0aa9d5733d5 100644
--- a/tests/baselines/reference/jsFileCompilationEmitBlockedCorrectly.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationEmitBlockedCorrectly.errors.txt
@@ -1,9 +1,9 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
-error TS5056: Cannot write file 'tests/cases/compiler/a.js' since one or more input files would emit into it.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+error TS5056: Cannot write file 'tests/cases/compiler/a.js' because it would be overwritten by multiple input files.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
-!!! error TS5056: Cannot write file 'tests/cases/compiler/a.js' since one or more input files would emit into it.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5056: Cannot write file 'tests/cases/compiler/a.js' because it would be overwritten by multiple input files.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationEnumSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationEnumSyntax.errors.txt
index e9fd9cc31b7..538dfb38972 100644
--- a/tests/baselines/reference/jsFileCompilationEnumSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationEnumSyntax.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,6): error TS8015: 'enum declarations' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     enum E { }
          ~
diff --git a/tests/baselines/reference/jsFileCompilationErrorOnDeclarationsWithJsFileReferenceWithNoOut.errors.txt b/tests/baselines/reference/jsFileCompilationErrorOnDeclarationsWithJsFileReferenceWithNoOut.errors.txt
index 433a3c6b7be..641731936f8 100644
--- a/tests/baselines/reference/jsFileCompilationErrorOnDeclarationsWithJsFileReferenceWithNoOut.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationErrorOnDeclarationsWithJsFileReferenceWithNoOut.errors.txt
@@ -1,9 +1,9 @@
 error TS5053: Option 'allowJs' cannot be specified with option 'declaration'.
-error TS5055: Cannot write file 'tests/cases/compiler/c.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/c.js' because it would overwrite input file.
 
 
 !!! error TS5053: Option 'allowJs' cannot be specified with option 'declaration'.
-!!! error TS5055: Cannot write file 'tests/cases/compiler/c.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/c.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationExportAssignmentSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationExportAssignmentSyntax.errors.txt
index 27371222dce..f537941c55c 100644
--- a/tests/baselines/reference/jsFileCompilationExportAssignmentSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationExportAssignmentSyntax.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,1): error TS8003: 'export=' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     export = b;
     ~~~~~~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationHeritageClauseSyntaxOfClass.errors.txt b/tests/baselines/reference/jsFileCompilationHeritageClauseSyntaxOfClass.errors.txt
index c7d080404a2..33b8a45f1aa 100644
--- a/tests/baselines/reference/jsFileCompilationHeritageClauseSyntaxOfClass.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationHeritageClauseSyntaxOfClass.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,9): error TS8005: 'implements clauses' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     class C implements D { }
             ~~~~~~~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationImportEqualsSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationImportEqualsSyntax.errors.txt
index 36ab7aab188..b4161367037 100644
--- a/tests/baselines/reference/jsFileCompilationImportEqualsSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationImportEqualsSyntax.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,1): error TS8002: 'import ... =' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     import a = b;
     ~~~~~~~~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationInterfaceSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationInterfaceSyntax.errors.txt
index 3089aeecb49..17fb8fcb187 100644
--- a/tests/baselines/reference/jsFileCompilationInterfaceSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationInterfaceSyntax.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,11): error TS8006: 'interface declarations' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     interface I { }
               ~
diff --git a/tests/baselines/reference/jsFileCompilationModuleSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationModuleSyntax.errors.txt
index d85819b8588..662028c53ed 100644
--- a/tests/baselines/reference/jsFileCompilationModuleSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationModuleSyntax.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,8): error TS8007: 'module declarations' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     module M { }
            ~
diff --git a/tests/baselines/reference/jsFileCompilationNoErrorWithoutDeclarationsWithJsFileReferenceWithNoOut.errors.txt b/tests/baselines/reference/jsFileCompilationNoErrorWithoutDeclarationsWithJsFileReferenceWithNoOut.errors.txt
index 06bfd61c7ab..f2f4142b993 100644
--- a/tests/baselines/reference/jsFileCompilationNoErrorWithoutDeclarationsWithJsFileReferenceWithNoOut.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationNoErrorWithoutDeclarationsWithJsFileReferenceWithNoOut.errors.txt
@@ -1,7 +1,7 @@
-error TS5055: Cannot write file 'tests/cases/compiler/c.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/c.js' because it would overwrite input file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/c.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/c.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationOptionalParameter.errors.txt b/tests/baselines/reference/jsFileCompilationOptionalParameter.errors.txt
index 6d9e3c5919d..295f827dd2d 100644
--- a/tests/baselines/reference/jsFileCompilationOptionalParameter.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationOptionalParameter.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,13): error TS8009: '?' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     function F(p?) { }
                 ~
diff --git a/tests/baselines/reference/jsFileCompilationPropertySyntaxOfClass.errors.txt b/tests/baselines/reference/jsFileCompilationPropertySyntaxOfClass.errors.txt
index 5a35e68bcec..fd5ea666459 100644
--- a/tests/baselines/reference/jsFileCompilationPropertySyntaxOfClass.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationPropertySyntaxOfClass.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,11): error TS8014: 'property declarations' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     class C { v }
               ~
diff --git a/tests/baselines/reference/jsFileCompilationPublicMethodSyntaxOfClass.errors.txt b/tests/baselines/reference/jsFileCompilationPublicMethodSyntaxOfClass.errors.txt
index a6d47e5fbe3..d67c9baea70 100644
--- a/tests/baselines/reference/jsFileCompilationPublicMethodSyntaxOfClass.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationPublicMethodSyntaxOfClass.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(2,5): error TS8009: 'public' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     class C {
         public foo() {
diff --git a/tests/baselines/reference/jsFileCompilationPublicParameterModifier.errors.txt b/tests/baselines/reference/jsFileCompilationPublicParameterModifier.errors.txt
index fa3e0e34a77..bc4913f6217 100644
--- a/tests/baselines/reference/jsFileCompilationPublicParameterModifier.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationPublicParameterModifier.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,23): error TS8012: 'parameter modifiers' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     class C { constructor(public x) { }}
                           ~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationReturnTypeSyntaxOfFunction.errors.txt b/tests/baselines/reference/jsFileCompilationReturnTypeSyntaxOfFunction.errors.txt
index 8b83a9d1f90..6dad5a29485 100644
--- a/tests/baselines/reference/jsFileCompilationReturnTypeSyntaxOfFunction.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationReturnTypeSyntaxOfFunction.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,15): error TS8010: 'types' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     function F(): number { }
                   ~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationSyntaxError.errors.txt b/tests/baselines/reference/jsFileCompilationSyntaxError.errors.txt
index b06375e8a6a..6e55ff30f04 100644
--- a/tests/baselines/reference/jsFileCompilationSyntaxError.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationSyntaxError.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(3,6): error TS1223: 'type' tag already specified.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     /**
       * @type {number}
diff --git a/tests/baselines/reference/jsFileCompilationTypeAliasSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationTypeAliasSyntax.errors.txt
index a0724e452b7..bc4d8e903ad 100644
--- a/tests/baselines/reference/jsFileCompilationTypeAliasSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeAliasSyntax.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,1): error TS8008: 'type aliases' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     type a = b;
     ~~~~~~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationTypeArgumentSyntaxOfCall.errors.txt b/tests/baselines/reference/jsFileCompilationTypeArgumentSyntaxOfCall.errors.txt
index acefc2ff569..8ac59196ed9 100644
--- a/tests/baselines/reference/jsFileCompilationTypeArgumentSyntaxOfCall.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeArgumentSyntaxOfCall.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,5): error TS8011: 'type arguments' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     Foo<number>();
         ~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationTypeAssertions.errors.txt b/tests/baselines/reference/jsFileCompilationTypeAssertions.errors.txt
index 50d6416a62b..e73ee46fb89 100644
--- a/tests/baselines/reference/jsFileCompilationTypeAssertions.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeAssertions.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,10): error TS8016: 'type assertion expressions' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     var v = <string>undefined;
              ~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationTypeOfParameter.errors.txt b/tests/baselines/reference/jsFileCompilationTypeOfParameter.errors.txt
index 69fa6251942..680b32a64f1 100644
--- a/tests/baselines/reference/jsFileCompilationTypeOfParameter.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeOfParameter.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,15): error TS8010: 'types' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     function F(a: number) { }
                   ~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfClass.errors.txt b/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfClass.errors.txt
index f279896c4ed..161c832ffd5 100644
--- a/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfClass.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfClass.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,9): error TS8004: 'type parameter declarations' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     class C<T> { }
             ~
diff --git a/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfFunction.errors.txt b/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfFunction.errors.txt
index 9b056bcae50..d7626f68564 100644
--- a/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfFunction.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfFunction.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,12): error TS8004: 'type parameter declarations' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     function F<T>() { }
                ~
diff --git a/tests/baselines/reference/jsFileCompilationTypeSyntaxOfVar.errors.txt b/tests/baselines/reference/jsFileCompilationTypeSyntaxOfVar.errors.txt
index 080cb580bf2..2c6ac3771be 100644
--- a/tests/baselines/reference/jsFileCompilationTypeSyntaxOfVar.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeSyntaxOfVar.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 tests/cases/compiler/a.js(1,8): error TS8010: 'types' can only be used in a .ts file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.js (1 errors) ====
     var v: () => number;
            ~~~~~~~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationWithDeclarationEmitPathSameAsInput.errors.txt b/tests/baselines/reference/jsFileCompilationWithDeclarationEmitPathSameAsInput.errors.txt
index a9c60c0748f..84900bccc88 100644
--- a/tests/baselines/reference/jsFileCompilationWithDeclarationEmitPathSameAsInput.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithDeclarationEmitPathSameAsInput.errors.txt
@@ -1,7 +1,7 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.d.ts' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/a.d.ts' because it would overwrite input file.
 
 
-!!! error TS5055: Cannot write file 'a.d.ts' which is one of the input files.
+!!! error TS5055: Cannot write file 'a.d.ts' because it would overwrite input file.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationWithJsEmitPathSameAsInput.errors.txt b/tests/baselines/reference/jsFileCompilationWithJsEmitPathSameAsInput.errors.txt
index 134c95dee15..4cc2cc2ab45 100644
--- a/tests/baselines/reference/jsFileCompilationWithJsEmitPathSameAsInput.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithJsEmitPathSameAsInput.errors.txt
@@ -1,9 +1,9 @@
-error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
-error TS5056: Cannot write file 'tests/cases/compiler/a.js' since one or more input files would emit into it.
+error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+error TS5056: Cannot write file 'tests/cases/compiler/a.js' because it would be overwritten by multiple input files.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' which is one of the input files.
-!!! error TS5056: Cannot write file 'tests/cases/compiler/a.js' since one or more input files would emit into it.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5056: Cannot write file 'tests/cases/compiler/a.js' because it would be overwritten by multiple input files.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationWithMapFileAsJs.errors.txt b/tests/baselines/reference/jsFileCompilationWithMapFileAsJs.errors.txt
index a97dc2c3cd6..06186b9f0b2 100644
--- a/tests/baselines/reference/jsFileCompilationWithMapFileAsJs.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithMapFileAsJs.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/b.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
 error TS6054: File 'tests/cases/compiler/b.js.map' has unsupported extension. The only supported extensions are '.ts', '.tsx', '.d.ts', '.js', '.jsx'.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/b.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
 !!! error TS6054: File 'tests/cases/compiler/b.js.map' has unsupported extension. The only supported extensions are '.ts', '.tsx', '.d.ts', '.js', '.jsx'.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     
diff --git a/tests/baselines/reference/jsFileCompilationWithMapFileAsJsWithInlineSourceMap.errors.txt b/tests/baselines/reference/jsFileCompilationWithMapFileAsJsWithInlineSourceMap.errors.txt
index a97dc2c3cd6..06186b9f0b2 100644
--- a/tests/baselines/reference/jsFileCompilationWithMapFileAsJsWithInlineSourceMap.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithMapFileAsJsWithInlineSourceMap.errors.txt
@@ -1,8 +1,8 @@
-error TS5055: Cannot write file 'tests/cases/compiler/b.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
 error TS6054: File 'tests/cases/compiler/b.js.map' has unsupported extension. The only supported extensions are '.ts', '.tsx', '.d.ts', '.js', '.jsx'.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/b.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
 !!! error TS6054: File 'tests/cases/compiler/b.js.map' has unsupported extension. The only supported extensions are '.ts', '.tsx', '.d.ts', '.js', '.jsx'.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     
diff --git a/tests/baselines/reference/jsFileCompilationWithOutDeclarationFileNameSameAsInputJsFile.errors.txt b/tests/baselines/reference/jsFileCompilationWithOutDeclarationFileNameSameAsInputJsFile.errors.txt
index ed23a30c3fa..826f906538f 100644
--- a/tests/baselines/reference/jsFileCompilationWithOutDeclarationFileNameSameAsInputJsFile.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithOutDeclarationFileNameSameAsInputJsFile.errors.txt
@@ -1,7 +1,7 @@
-error TS5055: Cannot write file 'tests/cases/compiler/b.d.ts' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/b.d.ts' because it would overwrite input file.
 
 
-!!! error TS5055: Cannot write file 'b.d.ts' which is one of the input files.
+!!! error TS5055: Cannot write file 'b.d.ts' because it would overwrite input file.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationWithOutFileNameSameAsInputJsFile.errors.txt b/tests/baselines/reference/jsFileCompilationWithOutFileNameSameAsInputJsFile.errors.txt
index 3531296e019..0f6852b21a0 100644
--- a/tests/baselines/reference/jsFileCompilationWithOutFileNameSameAsInputJsFile.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithOutFileNameSameAsInputJsFile.errors.txt
@@ -1,7 +1,7 @@
-error TS5055: Cannot write file 'tests/cases/compiler/b.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/b.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationWithoutOut.errors.txt b/tests/baselines/reference/jsFileCompilationWithoutOut.errors.txt
index 3531296e019..0f6852b21a0 100644
--- a/tests/baselines/reference/jsFileCompilationWithoutOut.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithoutOut.errors.txt
@@ -1,7 +1,7 @@
-error TS5055: Cannot write file 'tests/cases/compiler/b.js' which is one of the input files.
+error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
 
 
-!!! error TS5055: Cannot write file 'tests/cases/compiler/b.js' which is one of the input files.
+!!! error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }