Don't error on referenced project's noEmit if program has empty files (#1614)

Author: gabritto

internal/compiler/program.go

@@ -862,7 +862,7 @@ func (p *Program) verifyProjectReferences() {
 		}
 		refOptions := config.CompilerOptions()
 		if !refOptions.Composite.IsTrue() || refOptions.NoEmit.IsTrue() {
-			if len(config.FileNames()) > 0 {
+			if len(parent.FileNames()) > 0 {
 				if !refOptions.Composite.IsTrue() {
 					createDiagnosticForReference(parent, index, diagnostics.Referenced_project_0_must_have_setting_composite_Colon_true, ref.Path)
 				}

internal/execute/tsc_test.go

@@ -122,6 +122,30 @@ func TestTscCommandline(t *testing.T) {
 			subScenario:     "Parse watch interval option without tsconfig.json",
 			commandLineArgs: []string{"-w", "--watchInterval", "1000"},
 		},
+		{
+			subScenario: "Config with references and empty file and refers to config with noEmit",
+			files: FileMap{
+				"/home/src/workspaces/project/tsconfig.json": stringtestutil.Dedent(`{
+					"files": [],
+					"references": [
+						{
+							"path": "./packages/pkg1"
+						},
+					],
+				}`),
+				"/home/src/workspaces/project/packages/pkg1/tsconfig.json": stringtestutil.Dedent(`{
+					"compilerOptions": {
+						"composite": true,
+						"noEmit": true
+					},
+					"files": [
+						"./index.ts",
+					],
+				}`),
+				"/home/src/workspaces/project/packages/pkg1/index.ts": `export const a = 1;`,
+			},
+			commandLineArgs: []string{"-p", "."},
+		},
 	}
 
 	for _, testCase := range testCases {

testdata/baselines/reference/tsc/commandLine/Config-with-references-and-empty-file-and-refers-to-config-with-noEmit.js

@@ -0,0 +1,29 @@
+currentDirectory::/home/src/workspaces/project
+useCaseSensitiveFileNames::true
+Input::
+//// [/home/src/workspaces/project/packages/pkg1/index.ts] *new* 
+export const a = 1;
+//// [/home/src/workspaces/project/packages/pkg1/tsconfig.json] *new* 
+{
+                    "compilerOptions": {
+                        "composite": true,
+                        "noEmit": true
+                    },
+                    "files": [
+                        "./index.ts",
+                    ],
+                }
+//// [/home/src/workspaces/project/tsconfig.json] *new* 
+{
+                    "files": [],
+                    "references": [
+                        {
+                            "path": "./packages/pkg1"
+                        },
+                    ],
+                }
+
+tsgo -p .
+ExitStatus:: Success
+Output::
+