[clangd] When querying drivers by binary, look in PATH too

Sometimes compile_commands.json databases are created without an
absolute path for the driver in the command field. By default the driver
name is appended to the current directory, however if no driver is found
in that location assume it was in the default PATH and try finding it
there

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D93600

Author: rapgenic

clang-tools-extra/clangd/QueryDriverDatabase.cpp

@@ -136,10 +136,26 @@ llvm::Optional<DriverInfo> parseDriverOutput(llvm::StringRef Output) {
 }
 
 llvm::Optional<DriverInfo>
-extractSystemIncludesAndTarget(PathRef Driver, llvm::StringRef Lang,
+extractSystemIncludesAndTarget(llvm::SmallString<128> Driver,
+                               llvm::StringRef Lang,
                                llvm::ArrayRef<std::string> CommandLine,
                                const llvm::Regex &QueryDriverRegex) {
   trace::Span Tracer("Extract system includes and target");
+
+  if (!llvm::sys::path::is_absolute(Driver)) {
+    assert(llvm::none_of(
+        Driver, [](char C) { return llvm::sys::path::is_separator(C); }));
+    auto DriverProgram = llvm::sys::findProgramByName(Driver);
+    if (DriverProgram) {
+      vlog("System include extraction: driver {0} expanded to {1}", Driver,
+           *DriverProgram);
+      Driver = *DriverProgram;
+    } else {
+      elog("System include extraction: driver {0} not found in PATH", Driver);
+      return llvm::None;
+    }
+  }
+
   SPAN_ATTACH(Tracer, "driver", Driver);
   SPAN_ATTACH(Tracer, "lang", Lang);
 
@@ -332,7 +348,11 @@ class QueryDriverDatabase : public GlobalCompilationDatabase {
     }
 
     llvm::SmallString<128> Driver(Cmd->CommandLine.front());
-    llvm::sys::fs::make_absolute(Cmd->Directory, Driver);
+    if (llvm::any_of(Driver,
+                       [](char C) { return llvm::sys::path::is_separator(C); }))
+      // Driver is a not a single executable name but instead a path (either
+      // relative or absolute).
+      llvm::sys::fs::make_absolute(Cmd->Directory, Driver);
 
     if (auto Info =
             QueriedDrivers.get(/*Key=*/(Driver + ":" + Lang).str(), [&] {

clang-tools-extra/clangd/test/system-include-extractor.test

@@ -3,21 +3,24 @@
 # The mock driver below is a shell script:
 # REQUIRES: shell
 
+# Create a bin directory to store the mock-driver and add it to the path
+# RUN: mkdir -p %t.dir/bin
+# RUN: export PATH=%t.dir/bin:$PATH
 # Generate a mock-driver that will print %temp_dir%/my/dir and
 # %temp_dir%/my/dir2 as include search paths.
-# RUN: echo '#!/bin/sh' >> %t.dir/my_driver.sh
-# RUN: echo '[ "$0" = "%t.dir/my_driver.sh" ] || exit' >> %t.dir/my_driver.sh
-# RUN: echo 'args="$*"' >> %t.dir/my_driver.sh
-# RUN: echo '[ -z "${args##*"-nostdinc"*}" ] || exit' >> %t.dir/my_driver.sh
-# RUN: echo '[ -z "${args##*"-isysroot=/isysroot"*}" ] || exit' >> %t.dir/my_driver.sh
-# RUN: echo 'echo " $* " | grep " --sysroot /my/sysroot/path " || exit' >> %t.dir/my_driver.sh
-# RUN: echo 'echo line to ignore >&2' >> %t.dir/my_driver.sh
-# RUN: echo 'printf "Target: arm-linux-gnueabihf\r\n" >&2' >> %t.dir/my_driver.sh
-# RUN: echo 'printf "#include <...> search starts here:\r\n" >&2' >> %t.dir/my_driver.sh
-# RUN: echo 'echo %t.dir/my/dir/ >&2' >> %t.dir/my_driver.sh
-# RUN: echo 'echo %t.dir/my/dir2/ >&2' >> %t.dir/my_driver.sh
-# RUN: echo 'printf "End of search list.\r\n" >&2' >> %t.dir/my_driver.sh
-# RUN: chmod +x %t.dir/my_driver.sh
+# RUN: echo '#!/bin/sh' >> %t.dir/bin/my_driver.sh
+# RUN: echo '[ "$0" = "%t.dir/bin/my_driver.sh" ] || exit' >> %t.dir/bin/my_driver.sh
+# RUN: echo 'args="$*"' >> %t.dir/bin/my_driver.sh
+# RUN: echo '[ -z "${args##*"-nostdinc"*}" ] || exit' >> %t.dir/bin/my_driver.sh
+# RUN: echo '[ -z "${args##*"-isysroot=/isysroot"*}" ] || exit' >> %t.dir/bin/my_driver.sh
+# RUN: echo 'echo " $* " | grep " --sysroot /my/sysroot/path " || exit' >> %t.dir/bin/my_driver.sh
+# RUN: echo 'echo line to ignore >&2' >> %t.dir/bin/my_driver.sh
+# RUN: echo 'printf "Target: arm-linux-gnueabihf\r\n" >&2' >> %t.dir/bin/my_driver.sh
+# RUN: echo 'printf "#include <...> search starts here:\r\n" >&2' >> %t.dir/bin/my_driver.sh
+# RUN: echo 'echo %t.dir/my/dir/ >&2' >> %t.dir/bin/my_driver.sh
+# RUN: echo 'echo %t.dir/my/dir2/ >&2' >> %t.dir/bin/my_driver.sh
+# RUN: echo 'printf "End of search list.\r\n" >&2' >> %t.dir/bin/my_driver.sh
+# RUN: chmod +x %t.dir/bin/my_driver.sh
 
 # Create header files my/dir/a.h and my/dir2/b.h
 # RUN: mkdir -p %t.dir/my/dir
@@ -27,7 +30,7 @@
 
 # Generate a compile_commands.json that will query the mock driver we've
 # created. Which should add a.h and b.h into include search path.
-# RUN: echo '[{"directory": "%/t.dir", "command": "%/t.dir/my_driver.sh the-file.cpp -nostdinc --sysroot /my/sysroot/path -isysroot=/isysroot", "file": "the-file.cpp"}]' > %t.dir/compile_commands.json
+# RUN: echo '[{"directory": "%/t.dir", "command": "my_driver.sh the-file.cpp -nostdinc --sysroot /my/sysroot/path -isysroot=/isysroot", "file": "the-file.cpp"}]' > %t.dir/compile_commands.json
 
 # RUN: sed -e "s|INPUT_DIR|%/t.dir|g" %s > %t.test.1
 # On Windows, we need the URI in didOpen to look like "uri":"file:///C:/..."