3 files changed, 31 insertions, 6 deletions
diff --git a/cli/tsc/00_typescript.js b/cli/tsc/00_typescript.js
index 8bd168cd3..a54ab1e32 100644
--- a/cli/tsc/00_typescript.js
+++ b/cli/tsc/00_typescript.js
@@ -38066,6 +38066,7 @@ ${lanes.join("\n")}
           name: "allowImportingTsExtensions",
           type: "boolean",
           affectsSemanticDiagnostics: true,
+          affectsBuildInfo: true,
           category: Diagnostics.Modules,
           description: Diagnostics.Allow_imports_to_include_TypeScript_file_extensions_Requires_moduleResolution_bundler_and_either_noEmit_or_emitDeclarationOnly_to_be_set,
           defaultValueDescription: false
@@ -120426,7 +120427,7 @@ ${lanes.join("\n")}
       const { optionsNameMap } = getOptionsNameMap();
       for (const name of getOwnKeys(options).sort(compareStringsCaseSensitive)) {
         const optionInfo = optionsNameMap.get(name.toLowerCase());
-        if (optionInfo == null ? void 0 : optionInfo.affectsBuildInfo) {
+        if (optionInfo && (optionInfo.affectsBuildInfo || optionInfo.affectsSemanticDiagnostics)) {
           (result || (result = {}))[name] = convertToReusableCompilerOptionValue(
             optionInfo,
             options[name],
diff --git a/cli/tsc/99_main_compiler.js b/cli/tsc/99_main_compiler.js
index cb844624c..c7df8e85d 100644
--- a/cli/tsc/99_main_compiler.js
+++ b/cli/tsc/99_main_compiler.js
@@ -328,7 +328,7 @@ delete Object.prototype.__proto__;
     }
   }
 
-  /** @param {ts.Diagnostic[]} diagnostics */
+  /** @param {readonly ts.Diagnostic[]} diagnostics */
   function fromTypeScriptDiagnostic(diagnostics) {
     return diagnostics.map(({ relatedInformation: ri, source, ...diag }) => {
       /** @type {any} */
@@ -750,6 +750,7 @@ delete Object.prototype.__proto__;
    * @property {Record<string, any>} config
    * @property {boolean} debug
    * @property {string[]} rootNames
+   * @property {boolean} localOnly
    */
 
   /**
@@ -776,7 +777,7 @@ delete Object.prototype.__proto__;
   /** The API that is called by Rust when executing a request.
    * @param {Request} request
    */
-  function exec({ config, debug: debugFlag, rootNames }) {
+  function exec({ config, debug: debugFlag, rootNames, localOnly }) {
     setLogDebug(debugFlag, "TS");
     performanceStart();
     if (logDebug) {
@@ -800,12 +801,31 @@ delete Object.prototype.__proto__;
       configFileParsingDiagnostics,
     });
 
+    const checkFiles = localOnly
+      ? rootNames
+        .filter((n) => !n.startsWith("http"))
+        .map((checkName) => {
+          const sourceFile = program.getSourceFile(checkName);
+          if (sourceFile == null) {
+            throw new Error("Could not find source file for: " + checkName);
+          }
+          return sourceFile;
+        })
+      : undefined;
     const diagnostics = [
       ...program.getConfigFileParsingDiagnostics(),
-      ...program.getSyntacticDiagnostics(),
+      ...(checkFiles == null
+        ? program.getSyntacticDiagnostics()
+        : ts.sortAndDeduplicateDiagnostics(
+          checkFiles.map((s) => program.getSyntacticDiagnostics(s)).flat(),
+        )),
       ...program.getOptionsDiagnostics(),
       ...program.getGlobalDiagnostics(),
-      ...program.getSemanticDiagnostics(),
+      ...(checkFiles == null
+        ? program.getSemanticDiagnostics()
+        : ts.sortAndDeduplicateDiagnostics(
+          checkFiles.map((s) => program.getSemanticDiagnostics(s)).flat(),
+        )),
     ].filter((diagnostic) => !IGNORED_DIAGNOSTICS.includes(diagnostic.code));
 
     // emit the tsbuildinfo file
@@ -867,7 +887,7 @@ delete Object.prototype.__proto__;
           allowNonTsExtensions: true,
           allowImportingTsExtensions: true,
         });
-        if (errors.length) {
+        if (errors.length > 0 && logDebug) {
           debug(ts.formatDiagnostics(errors, host));
         }
         compilationSettings = options;
diff --git a/cli/tsc/mod.rs b/cli/tsc/mod.rs
index 43fccb37e..2f2015542 100644
--- a/cli/tsc/mod.rs
+++ b/cli/tsc/mod.rs
@@ -1,6 +1,7 @@
 // Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
 
 use crate::args::TsConfig;
+use crate::args::TypeCheckMode;
 use crate::node;
 use crate::node::node_resolve_npm_reference;
 use crate::node::NodeResolution;
@@ -308,6 +309,7 @@ pub struct Request {
   /// A vector of strings that represent the root/entry point modules for the
   /// program.
   pub root_names: Vec<(ModuleSpecifier, MediaType)>,
+  pub check_mode: TypeCheckMode,
 }
 
 #[derive(Debug, Clone, Eq, PartialEq)]
@@ -806,6 +808,7 @@ pub fn exec(request: Request) -> Result<Response, AnyError> {
     "config": request.config,
     "debug": request.debug,
     "rootNames": root_names,
+    "localOnly": request.check_mode == TypeCheckMode::Local,
   });
   let request_str = request_value.to_string();
   let exec_source = format!("globalThis.exec({request_str})");
@@ -962,6 +965,7 @@ mod tests {
       maybe_npm_resolver: None,
       maybe_tsbuildinfo: None,
       root_names: vec![(specifier.clone(), MediaType::TypeScript)],
+      check_mode: TypeCheckMode::All,
     };
     exec(request)
   }