diff --git a/packages/compiler-cli/ngcc/test/host/commonjs_host_spec.ts b/packages/compiler-cli/ngcc/test/host/commonjs_host_spec.ts
index 95be061397..051d4f273d 100644
--- a/packages/compiler-cli/ngcc/test/host/commonjs_host_spec.ts
+++ b/packages/compiler-cli/ngcc/test/host/commonjs_host_spec.ts
@@ -1273,7 +1273,7 @@ describe('CommonJsReflectionHost', () => {
 
       const fooNode =
           getDeclaration(program, FUNCTION_BODY_FILE.name, 'foo', isNamedFunctionDeclaration) !;
-      const fooDef = host.getDefinitionOfFunction(fooNode);
+      const fooDef = host.getDefinitionOfFunction(fooNode) !;
       expect(fooDef.node).toBe(fooNode);
       expect(fooDef.body !.length).toEqual(1);
       expect(fooDef.body ![0].getText()).toEqual(`return x;`);
@@ -1283,7 +1283,7 @@ describe('CommonJsReflectionHost', () => {
 
       const barNode =
           getDeclaration(program, FUNCTION_BODY_FILE.name, 'bar', isNamedFunctionDeclaration) !;
-      const barDef = host.getDefinitionOfFunction(barNode);
+      const barDef = host.getDefinitionOfFunction(barNode) !;
       expect(barDef.node).toBe(barNode);
       expect(barDef.body !.length).toEqual(1);
       expect(ts.isReturnStatement(barDef.body ![0])).toBeTruthy();
@@ -1296,7 +1296,7 @@ describe('CommonJsReflectionHost', () => {
 
       const bazNode =
           getDeclaration(program, FUNCTION_BODY_FILE.name, 'baz', isNamedFunctionDeclaration) !;
-      const bazDef = host.getDefinitionOfFunction(bazNode);
+      const bazDef = host.getDefinitionOfFunction(bazNode) !;
       expect(bazDef.node).toBe(bazNode);
       expect(bazDef.body !.length).toEqual(3);
       expect(bazDef.parameters.length).toEqual(1);
@@ -1305,7 +1305,7 @@ describe('CommonJsReflectionHost', () => {
 
       const quxNode =
           getDeclaration(program, FUNCTION_BODY_FILE.name, 'qux', isNamedFunctionDeclaration) !;
-      const quxDef = host.getDefinitionOfFunction(quxNode);
+      const quxDef = host.getDefinitionOfFunction(quxNode) !;
       expect(quxDef.node).toBe(quxNode);
       expect(quxDef.body !.length).toEqual(2);
       expect(quxDef.parameters.length).toEqual(1);