From 6ee759539af3d85413d1dc210bdf730f5d3aaa8f Mon Sep 17 00:00:00 2001
From: Qiongsi Wu <qiongsi_wu@apple.com>
Date: Fri, 14 Nov 2025 14:49:10 -0800
Subject: [PATCH 1/2] Add test coverage for stable dir during by-name lookups.

---
 .../modules-full-by-mult-mod-names.c          | 27 +++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/clang/test/ClangScanDeps/modules-full-by-mult-mod-names.c b/clang/test/ClangScanDeps/modules-full-by-mult-mod-names.c
index 030f7f3427810..e4248e226b7d3 100644
--- a/clang/test/ClangScanDeps/modules-full-by-mult-mod-names.c
+++ b/clang/test/ClangScanDeps/modules-full-by-mult-mod-names.c
@@ -22,20 +22,43 @@ module root1 { header "root1.h"}
 // This is here to verify that the "root" directory doesn't clash with name of
 // the "root" module.
 
+// Verify the stable dir path.
+//--- Sysroot/usr/include/SysA/module.modulemap
+module SysA {
+  header "SysA.h"
+}
+
+//--- Sysroot/usr/include/SysA/SysA.h
+int SysVal = 42;
+
 //--- cdb.json.template
 [{
   "file": "",
   "directory": "DIR",
-  "command": "clang -fmodules -fmodules-cache-path=DIR/cache -I DIR -x c"
+  "command": "clang -fmodules -fmodules-cache-path=DIR/cache -I DIR -isysroot DIR/Sysroot -IDIR/Sysroot/usr/include -x c"
 }]
 
 // RUN: sed "s|DIR|%/t|g" %t/cdb.json.template > %t/cdb.json
-// RUN: clang-scan-deps -compilation-database %t/cdb.json -format experimental-full -module-names=root,root1,direct > %t/result.json
+// RUN: clang-scan-deps -compilation-database %t/cdb.json -format experimental-full -module-names=SysA,root,root1,direct > %t/result.json
 // RUN: cat %t/result.json | sed 's:\\\\\?:/:g' | FileCheck -DPREFIX=%/t %s
 
 // CHECK:      {
 // CHECK-NEXT:   "modules": [
 // CHECK-NEXT:     {
+// CHECK-NEXT:       "is-in-stable-directories": true,
+// CHECK-NEXT:       "clang-module-deps": [],
+// CHECK-NEXT:       "clang-modulemap-file": "[[PREFIX]]/Sysroot/usr/include/SysA/module.modulemap",
+// CHECK-NEXT:       "command-line": [
+// CHECK:            ],
+// CHECK-NEXT:       "context-hash": "{{.*}}",
+// CHECK-NEXT:       "file-deps": [
+// CHECK-NEXT:         "[[PREFIX]]/Sysroot/usr/include/SysA/module.modulemap",
+// CHECK-NEXT:         "[[PREFIX]]/Sysroot/usr/include/SysA/SysA.h"
+// CHECK-NEXT:       ],
+// CHECK-NEXT:       "link-libraries": [],
+// CHECK-NEXT:       "name": "SysA"
+// CHECK-NEXT:     },
+// CHECK-NEXT:     {
 // CHECK-NEXT:       "clang-module-deps": [
 // CHECK-NEXT:         {
 // CHECK-NEXT:           "context-hash": "{{.*}}",

From dfb1a773cd823b6af1f61de6426e5e14df956ceb Mon Sep 17 00:00:00 2001
From: Qiongsi Wu <qiongsi_wu@apple.com>
Date: Fri, 14 Nov 2025 16:15:08 -0800
Subject: [PATCH 2/2] Have an individual stable dir test.

---
 .../module-in-stable-dir-by-name.c            | 43 +++++++++++++++++++
 .../modules-full-by-mult-mod-names.c          | 27 +-----------
 2 files changed, 45 insertions(+), 25 deletions(-)
 create mode 100644 clang/test/ClangScanDeps/module-in-stable-dir-by-name.c

diff --git a/clang/test/ClangScanDeps/module-in-stable-dir-by-name.c b/clang/test/ClangScanDeps/module-in-stable-dir-by-name.c
new file mode 100644
index 0000000000000..742bc2e046ceb
--- /dev/null
+++ b/clang/test/ClangScanDeps/module-in-stable-dir-by-name.c
@@ -0,0 +1,43 @@
+// UNSUPPORTED: system-windows
+// RUN: rm -rf %t
+// RUN: split-file %s %t
+
+// Verify the stable dir path.
+//--- Sysroot/usr/include/SysA/module.modulemap
+module SysA {
+  header "SysA.h"
+}
+
+//--- Sysroot/usr/include/SysA/SysA.h
+int SysVal = 42;
+
+//--- cdb.json.template
+[{
+  "file": "",
+  "directory": "DIR",
+  "command": "clang -fmodules -fmodules-cache-path=DIR/cache -isysroot DIR/Sysroot -IDIR/Sysroot/usr/include -x c"
+}]
+
+// RUN: sed "s|DIR|%/t|g" %t/cdb.json.template > %t/cdb.json
+// RUN: clang-scan-deps -compilation-database %t/cdb.json -format experimental-full -module-names=SysA > %t/result.json
+// RUN: cat %t/result.json | sed 's:\\\\\?:/:g' | FileCheck -DPREFIX=%/t %s
+
+// CHECK:      {
+// CHECK-NEXT:   "modules": [
+// CHECK-NEXT:     {
+// CHECK-NEXT:       "is-in-stable-directories": true,
+// CHECK-NEXT:       "clang-module-deps": [],
+// CHECK-NEXT:       "clang-modulemap-file": "[[PREFIX]]/Sysroot/usr/include/SysA/module.modulemap",
+// CHECK-NEXT:       "command-line": [
+// CHECK:            ],
+// CHECK-NEXT:       "context-hash": "{{.*}}",
+// CHECK-NEXT:       "file-deps": [
+// CHECK-NEXT:         "[[PREFIX]]/Sysroot/usr/include/SysA/module.modulemap",
+// CHECK-NEXT:         "[[PREFIX]]/Sysroot/usr/include/SysA/SysA.h"
+// CHECK-NEXT:       ],
+// CHECK-NEXT:       "link-libraries": [],
+// CHECK-NEXT:       "name": "SysA"
+// CHECK-NEXT:     }
+// CHECK-NEXT:   ],
+// CHECK-NEXT:   "translation-units": []
+// CHECK-NEXT: }
diff --git a/clang/test/ClangScanDeps/modules-full-by-mult-mod-names.c b/clang/test/ClangScanDeps/modules-full-by-mult-mod-names.c
index e4248e226b7d3..030f7f3427810 100644
--- a/clang/test/ClangScanDeps/modules-full-by-mult-mod-names.c
+++ b/clang/test/ClangScanDeps/modules-full-by-mult-mod-names.c
@@ -22,43 +22,20 @@ module root1 { header "root1.h"}
 // This is here to verify that the "root" directory doesn't clash with name of
 // the "root" module.
 
-// Verify the stable dir path.
-//--- Sysroot/usr/include/SysA/module.modulemap
-module SysA {
-  header "SysA.h"
-}
-
-//--- Sysroot/usr/include/SysA/SysA.h
-int SysVal = 42;
-
 //--- cdb.json.template
 [{
   "file": "",
   "directory": "DIR",
-  "command": "clang -fmodules -fmodules-cache-path=DIR/cache -I DIR -isysroot DIR/Sysroot -IDIR/Sysroot/usr/include -x c"
+  "command": "clang -fmodules -fmodules-cache-path=DIR/cache -I DIR -x c"
 }]
 
 // RUN: sed "s|DIR|%/t|g" %t/cdb.json.template > %t/cdb.json
-// RUN: clang-scan-deps -compilation-database %t/cdb.json -format experimental-full -module-names=SysA,root,root1,direct > %t/result.json
+// RUN: clang-scan-deps -compilation-database %t/cdb.json -format experimental-full -module-names=root,root1,direct > %t/result.json
 // RUN: cat %t/result.json | sed 's:\\\\\?:/:g' | FileCheck -DPREFIX=%/t %s
 
 // CHECK:      {
 // CHECK-NEXT:   "modules": [
 // CHECK-NEXT:     {
-// CHECK-NEXT:       "is-in-stable-directories": true,
-// CHECK-NEXT:       "clang-module-deps": [],
-// CHECK-NEXT:       "clang-modulemap-file": "[[PREFIX]]/Sysroot/usr/include/SysA/module.modulemap",
-// CHECK-NEXT:       "command-line": [
-// CHECK:            ],
-// CHECK-NEXT:       "context-hash": "{{.*}}",
-// CHECK-NEXT:       "file-deps": [
-// CHECK-NEXT:         "[[PREFIX]]/Sysroot/usr/include/SysA/module.modulemap",
-// CHECK-NEXT:         "[[PREFIX]]/Sysroot/usr/include/SysA/SysA.h"
-// CHECK-NEXT:       ],
-// CHECK-NEXT:       "link-libraries": [],
-// CHECK-NEXT:       "name": "SysA"
-// CHECK-NEXT:     },
-// CHECK-NEXT:     {
 // CHECK-NEXT:       "clang-module-deps": [
 // CHECK-NEXT:         {
 // CHECK-NEXT:           "context-hash": "{{.*}}",