diff --git a/deno/ts_morph.js b/deno/ts_morph.js
index 826b7c793..9ba703e16 100644
--- a/deno/ts_morph.js
+++ b/deno/ts_morph.js
@@ -403,7 +403,7 @@ class LazyReferenceCoordinator {
         if (!this.dirtySourceFiles.has(sourceFile))
             return;
         sourceFile._referenceContainer.refresh();
-        this.clearDityForSourceFile(sourceFile);
+        this.clearDirtyForSourceFile(sourceFile);
     }
     addDirtySourceFile(sourceFile) {
         this.dirtySourceFiles.add(sourceFile);
@@ -411,7 +411,7 @@ class LazyReferenceCoordinator {
     clearDirtySourceFiles() {
         this.dirtySourceFiles.clear();
     }
-    clearDityForSourceFile(sourceFile) {
+    clearDirtyForSourceFile(sourceFile) {
         this.dirtySourceFiles.delete(sourceFile);
     }
 }
@@ -17605,7 +17605,10 @@ class LanguageService {
             host: this._compilerHost,
             configFileParsingDiagnostics: params.configFileParsingDiagnostics,
         });
-        this._context.compilerFactory.onSourceFileAdded(() => this._reset());
+        this._context.compilerFactory.onSourceFileAdded(sourceFile => {
+            if (sourceFile._isInProject())
+                this._reset();
+        });
         this._context.compilerFactory.onSourceFileRemoved(() => this._reset());
     }
     get compilerObject() {
@@ -19233,11 +19236,10 @@ class CompilerFactory {
             wasAdded = true;
             return createdSourceFile;
         });
-        if (options.markInProject) {
+        if (options.markInProject)
             sourceFile._markAsInProject();
-            if (wasAdded)
-                this.sourceFileAddedEventContainer.fire(sourceFile);
-        }
+        if (wasAdded)
+            this.sourceFileAddedEventContainer.fire(sourceFile);
         return sourceFile;
     }
     addSourceFileToCache(sourceFile) {
diff --git a/packages/ts-morph/src/compiler/tools/LanguageService.ts b/packages/ts-morph/src/compiler/tools/LanguageService.ts
index db7f7ac94..cb78de9f2 100644
--- a/packages/ts-morph/src/compiler/tools/LanguageService.ts
+++ b/packages/ts-morph/src/compiler/tools/LanguageService.ts
@@ -71,7 +71,13 @@ export class LanguageService {
       configFileParsingDiagnostics: params.configFileParsingDiagnostics,
     });
 
-    this._context.compilerFactory.onSourceFileAdded(() => this._reset());
+    this._context.compilerFactory.onSourceFileAdded(sourceFile => {
+      // Only reset if the user is explicitly adding the source file.
+      // Otherwise it might have just been the TypeScript compiler
+      // doing some analysis and pulling in a new lib file or other file.
+      if (sourceFile._isInProject())
+        this._reset();
+    });
     this._context.compilerFactory.onSourceFileRemoved(() => this._reset());
   }
 
diff --git a/packages/ts-morph/src/factories/CompilerFactory.ts b/packages/ts-morph/src/factories/CompilerFactory.ts
index 898267ba4..2c29f3c9a 100644
--- a/packages/ts-morph/src/factories/CompilerFactory.ts
+++ b/packages/ts-morph/src/factories/CompilerFactory.ts
@@ -389,12 +389,11 @@ export class CompilerFactory {
         return createdSourceFile;
       });
 
-    if (options.markInProject) {
+    if (options.markInProject)
       sourceFile._markAsInProject();
 
-      if (wasAdded)
-        this.sourceFileAddedEventContainer.fire(sourceFile);
-    }
+    if (wasAdded)
+      this.sourceFileAddedEventContainer.fire(sourceFile);
 
     return sourceFile;
   }
diff --git a/packages/ts-morph/src/tests/issues/1227tests.ts b/packages/ts-morph/src/tests/issues/1227tests.ts
new file mode 100644
index 000000000..0ae89912d
--- /dev/null
+++ b/packages/ts-morph/src/tests/issues/1227tests.ts
@@ -0,0 +1,51 @@
+import { InMemoryFileSystemHost } from "@ts-morph/common";
+import { expect } from "chai";
+import { Project } from "../../Project";
+
+describe("tests for issue #1227", () => {
+  it("should find referencing source files", () => {
+    const fileSystem = new InMemoryFileSystemHost();
+    fileSystem.writeFileSync(
+      "/server.ts",
+      `import { run } from './mid'`,
+    );
+    fileSystem.writeFileSync(
+      "/mid.ts",
+      `import {A, B} from './constants';
+
+export function run() {
+  console.log(A, B);
+  return null as any;
+}
+`,
+    );
+    fileSystem.writeFileSync(
+      "/constants.ts",
+      `export const A = 'a';
+export const B = 'b';
+`,
+    );
+    fileSystem.writeFileSync(
+      "/tsconfig.json",
+      `{
+  "exclude": [
+    "node_modules"
+  ],
+  "compilerOptions": {
+    "module": "commonjs",
+    "target": "es6",
+    "outDir": "./dist",
+    "baseUrl": ".",
+  },
+  "files": [
+    "./server.ts",
+  ]
+}`,
+    );
+    const project = new Project({ fileSystem, tsConfigFilePath: "/tsconfig.json" });
+
+    const file = project.getSourceFileOrThrow("constants.ts");
+    expect(file.getReferencingNodesInOtherSourceFiles().map(n => n.getText()))
+      .to.deep.equal(["import {A, B} from './constants';"]);
+  });
+});
diff --git a/packages/ts-morph/src/utils/references/LazyReferenceCoordinator.ts b/packages/ts-morph/src/utils/references/LazyReferenceCoordinator.ts
index a13711940..86e50bb4a 100644
--- a/packages/ts-morph/src/utils/references/LazyReferenceCoordinator.ts
+++ b/packages/ts-morph/src/utils/references/LazyReferenceCoordinator.ts
@@ -34,7 +34,7 @@ export class LazyReferenceCoordinator {
     if (!this.dirtySourceFiles.has(sourceFile))
       return;
     sourceFile._referenceContainer.refresh();
-    this.clearDityForSourceFile(sourceFile);
+    this.clearDirtyForSourceFile(sourceFile);
   }
 
   addDirtySourceFile(sourceFile: SourceFile) {
@@ -45,7 +45,7 @@ export class LazyReferenceCoordinator {
     this.dirtySourceFiles.clear();
   }
 
-  clearDityForSourceFile(sourceFile: SourceFile) {
+  clearDirtyForSourceFile(sourceFile: SourceFile) {
     this.dirtySourceFiles.delete(sourceFile);
   }
 }