Fix the error filtering

Author: sheetalkamat

internal/compiler/program.go

@@ -433,7 +433,8 @@ func (p *Program) GetIncludeProcessorDiagnostics(sourceFile *ast.SourceFile) []*
 	if checker.SkipTypeChecking(sourceFile, p.Options(), p, false) {
 		return nil
 	}
-	return p.includeProcessor.getDiagnostics(p).GetDiagnosticsForFile(sourceFile.FileName())
+	filtered, _ := p.getDiagnosticsWithPrecedingDirectives(sourceFile, p.includeProcessor.getDiagnostics(p).GetDiagnosticsForFile(sourceFile.FileName()))
+	return filtered
 }
 
 func (p *Program) getSourceFilesToEmit(targetSourceFile *ast.SourceFile, forceDtsEmit bool) []*ast.SourceFile {
@@ -1058,8 +1059,20 @@ func (p *Program) getSemanticDiagnosticsForFileNotFilter(ctx context.Context, so
 		})
 	}
 
-	if len(sourceFile.CommentDirectives) == 0 {
-		return diags
+	filtered, directivesByLine := p.getDiagnosticsWithPrecedingDirectives(sourceFile, diags)
+	for _, directive := range directivesByLine {
+		// Above we changed all used directive kinds to @ts-ignore, so any @ts-expect-error directives that
+		// remain are unused and thus errors.
+		if directive.Kind == ast.CommentDirectiveKindExpectError {
+			filtered = append(filtered, ast.NewDiagnostic(sourceFile, directive.Loc, diagnostics.Unused_ts_expect_error_directive))
+		}
+	}
+	return filtered
+}
+
+func (p *Program) getDiagnosticsWithPrecedingDirectives(sourceFile *ast.SourceFile, diags []*ast.Diagnostic) ([]*ast.Diagnostic, map[int]ast.CommentDirective) {
+	if len(diags) == 0 || len(sourceFile.CommentDirectives) == 0 {
+		return diags, nil
 	}
 	// Build map of directives by line number
 	directivesByLine := make(map[int]ast.CommentDirective)
@@ -1089,14 +1102,7 @@ func (p *Program) getSemanticDiagnosticsForFileNotFilter(ctx context.Context, so
 			filtered = append(filtered, diagnostic)
 		}
 	}
-	for _, directive := range directivesByLine {
-		// Above we changed all used directive kinds to @ts-ignore, so any @ts-expect-error directives that
-		// remain are unused and thus errors.
-		if directive.Kind == ast.CommentDirectiveKindExpectError {
-			filtered = append(filtered, ast.NewDiagnostic(sourceFile, directive.Loc, diagnostics.Unused_ts_expect_error_directive))
-		}
-	}
-	return filtered
+	return filtered, directivesByLine
 }
 
 func (p *Program) getDeclarationDiagnosticsForFile(ctx context.Context, sourceFile *ast.SourceFile) []*ast.Diagnostic {