Ninja: Transform DEPFILEs with policy CMP0116

Fixes: #21267

3 files changed, 52 insertions, 3 deletions

diff --git a/Source/cmGlobalNinjaGenerator.h b/Source/cmGlobalNinjaGenerator.h
index 884a711..ec001d3 100644
--- a/Source/cmGlobalNinjaGenerator.h
+++ b/Source/cmGlobalNinjaGenerator.h
@@ -24,6 +24,7 @@
 #include "cmNinjaTypes.h"
 #include "cmPolicies.h"
 #include "cmStringAlgorithms.h"
+#include "cmTransformDepfile.h"
 
 class cmCustomCommand;
 class cmGeneratorTarget;
@@ -211,6 +212,10 @@ public:
   const char* GetCleanTargetName() const override { return "clean"; }
 
   bool SupportsCustomCommandDepfile() const override { return true; }
+  cm::optional<cmDepfileFormat> DepfileFormat() const override
+  {
+    return cmDepfileFormat::GccDepfile;
+  }
 
   virtual cmGeneratedFileStream* GetImplFileStream(
     const std::string& /*config*/) const
diff --git a/Source/cmLocalNinjaGenerator.cxx b/Source/cmLocalNinjaGenerator.cxx
index ad782ee..ce85320 100644
--- a/Source/cmLocalNinjaGenerator.cxx
+++ b/Source/cmLocalNinjaGenerator.cxx
@@ -22,7 +22,9 @@
 #include "cmGlobalNinjaGenerator.h"
 #include "cmLocalGenerator.h"
 #include "cmMakefile.h"
+#include "cmMessageType.h"
 #include "cmNinjaTargetGenerator.h"
+#include "cmPolicies.h"
 #include "cmProperty.h"
 #include "cmRulePlaceholderExpander.h"
 #include "cmSourceFile.h"
@@ -573,7 +575,20 @@ void cmLocalNinjaGenerator::WriteCustomCommandBuildStatement(
     return;
   }
 
-  cmCustomCommandGenerator ccg(*cc, config, this);
+  bool transformDepfile = false;
+  auto cmp0116 = this->GetPolicyStatus(cmPolicies::CMP0116);
+  switch (cmp0116) {
+    case cmPolicies::OLD:
+    case cmPolicies::WARN:
+      break;
+    case cmPolicies::REQUIRED_IF_USED:
+    case cmPolicies::REQUIRED_ALWAYS:
+    case cmPolicies::NEW:
+      transformDepfile = true;
+      break;
+  }
+
+  cmCustomCommandGenerator ccg(*cc, config, this, transformDepfile);
 
   const std::vector<std::string>& outputs = ccg.GetOutputs();
   const std::vector<std::string>& byproducts = ccg.GetByproducts();
@@ -623,10 +638,36 @@ void cmLocalNinjaGenerator::WriteCustomCommandBuildStatement(
     cmCryptoHash hash(cmCryptoHash::AlgoSHA256);
     customStep += hash.HashString(ninjaOutputs[0]).substr(0, 7);
 
+    std::string depfile = cc->GetDepfile();
+    if (!depfile.empty()) {
+      switch (cmp0116) {
+        case cmPolicies::WARN:
+          if (this->GetCurrentBinaryDirectory() !=
+                this->GetBinaryDirectory() ||
+              this->Makefile->PolicyOptionalWarningEnabled(
+                "CMAKE_POLICY_WARNING_CMP0116")) {
+            this->GetCMakeInstance()->IssueMessage(
+              MessageType::AUTHOR_WARNING,
+              cmPolicies::GetPolicyWarning(cmPolicies::CMP0116),
+              cc->GetBacktrace());
+          }
+          CM_FALLTHROUGH;
+        case cmPolicies::OLD:
+          break;
+        case cmPolicies::REQUIRED_IF_USED:
+        case cmPolicies::REQUIRED_ALWAYS:
+        case cmPolicies::NEW:
+          cmSystemTools::MakeDirectory(
+            cmStrCat(this->GetBinaryDirectory(), "/CMakeFiles/d"));
+          depfile = ccg.GetInternalDepfile();
+          break;
+      }
+    }
+
     gg->WriteCustomCommandBuild(
       this->BuildCommandLine(cmdLines, customStep),
       this->ConstructComment(ccg), "Custom command for " + ninjaOutputs[0],
-      cc->GetDepfile(), cc->GetJobPool(), cc->GetUsesTerminal(),
+      depfile, cc->GetJobPool(), cc->GetUsesTerminal(),
       /*restat*/ !symbolic || !byproducts.empty(), ninjaOutputs, config,
       ninjaDeps, orderOnlyDeps);
   }
diff --git a/Source/cmPolicies.h b/Source/cmPolicies.h
index f9f7d0e..99bac98 100644
--- a/Source/cmPolicies.h
+++ b/Source/cmPolicies.h
@@ -342,7 +342,10 @@ class cmMakefile;
          "ExternalProject step targets fully adopt their steps.", 3, 19, 0,   \
          cmPolicies::WARN)                                                    \
   SELECT(POLICY, CMP0115, "Source file extensions must be explicit.", 3, 20,  \
-         0, cmPolicies::WARN)
+         0, cmPolicies::WARN)                                                 \
+  SELECT(POLICY, CMP0116,                                                     \
+         "Ninja generators transform DEPFILEs from add_custom_command().", 3, \
+         20, 0, cmPolicies::WARN)
 
 #define CM_SELECT_ID(F, A1, A2, A3, A4, A5, A6) F(A1)
 #define CM_FOR_EACH_POLICY_ID(POLICY)                                         \