From d3c0da48d9b17d48ffcfe76a0915906d7c532db6 Mon Sep 17 00:00:00 2001
From: Harmen Stoppels <harmenstoppels@gmail.com>
Date: Fri, 29 Sep 2023 16:40:21 +0200
Subject: [PATCH] Don't drop build deps on overwrite install (#40252)

If you `spack install x ^y` where `y` is a pure build dep of `x`, and
then uninstall `y`, and then `spack install --overwrite x ^y`, the build
fails because `y` is not re-installed.

Same can happen when you install a develop spec, run `spack gc`,
modify sources, and install again; develop specs rely on overwrite
install to work correctly.
---
 lib/spack/spack/installer.py      |  9 +++++----
 lib/spack/spack/test/installer.py | 24 ++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/lib/spack/spack/installer.py b/lib/spack/spack/installer.py
index 3329b1a1ca3..5c529b08d38 100644
--- a/lib/spack/spack/installer.py
+++ b/lib/spack/spack/installer.py
@@ -2436,10 +2436,11 @@ def get_deptypes(self, pkg):
         else:
             cache_only = self.install_args.get("dependencies_cache_only")
 
-        # Include build dependencies if pkg is not installed and cache_only
-        # is False, or if build depdencies are explicitly called for
-        # by include_build_deps.
-        if include_build_deps or not (cache_only or pkg.spec.installed):
+        # Include build dependencies if pkg is going to be built from sources, or
+        # if build deps are explicitly requested.
+        if include_build_deps or not (
+            cache_only or pkg.spec.installed and not pkg.spec.dag_hash() in self.overwrite
+        ):
             deptypes.append("build")
         if self.run_tests(pkg):
             deptypes.append("test")
diff --git a/lib/spack/spack/test/installer.py b/lib/spack/spack/test/installer.py
index 7b9c2b5184d..ba99c904841 100644
--- a/lib/spack/spack/test/installer.py
+++ b/lib/spack/spack/test/installer.py
@@ -1386,6 +1386,30 @@ def test_single_external_implicit_install(install_mockery, explicit_args, is_exp
     assert spack.store.db.get_record(pkg).explicit == is_explicit
 
 
+@pytest.mark.skipif(
+    sys.platform == "win32",
+    reason="Windows breaks overwrite install due to prefix normalization inconsistencies",
+)
+def test_overwrite_install_does_install_build_deps(install_mockery, mock_fetch):
+    """When overwrite installing something from sources, build deps should be installed."""
+    s = spack.spec.Spec("dtrun3").concretized()
+    create_installer([(s, {})]).install()
+
+    # Verify there is a pure build dep
+    edge = s.edges_to_dependencies(name="dtbuild3").pop()
+    assert edge.deptypes == ("build",)
+    build_dep = edge.spec
+
+    # Uninstall the build dep
+    build_dep.package.do_uninstall()
+
+    # Overwrite install the root dtrun3
+    create_installer([(s, {"overwrite": [s.dag_hash()]})]).install()
+
+    # Verify that the build dep was also installed.
+    assert build_dep.installed
+
+
 @pytest.mark.parametrize("run_tests", [True, False])
 def test_print_install_test_log_skipped(install_mockery, mock_packages, capfd, run_tests):
     """Confirm printing of install log skipped if not run/no failures."""