From 77cd74a3ea964fa390d85c371902387e9ffc4a92 Mon Sep 17 00:00:00 2001
From: Ashley Whetter <ashley@awhetter.co.uk>
Date: Sun, 17 Jan 2016 22:09:30 +0000
Subject: [PATCH] Print line number of cache parse errors (#11109)

Track the line number while parsing `CMakeCache.txt` files and include
it in a parse failure error message.
---
 Source/cmCacheManager.cxx                              | 10 ++++++++--
 Tests/RunCMake/CommandLine/RunCMakeTest.cmake          |  5 +++++
 Tests/RunCMake/CommandLine/cache-bad-entry-result.txt  |  1 +
 Tests/RunCMake/CommandLine/cache-bad-entry-stderr.txt  |  1 +
 .../CommandLine/cache-bad-entry/CMakeCache.txt         | 10 ++++++++++
 .../RunCMake/CommandLine/cache-empty-entry-result.txt  |  1 +
 .../RunCMake/CommandLine/cache-empty-entry-stderr.txt  |  1 +
 .../CommandLine/cache-empty-entry/CMakeCache.txt       |  7 +++++++
 8 files changed, 34 insertions(+), 2 deletions(-)
 create mode 100644 Tests/RunCMake/CommandLine/cache-bad-entry-result.txt
 create mode 100644 Tests/RunCMake/CommandLine/cache-bad-entry-stderr.txt
 create mode 100644 Tests/RunCMake/CommandLine/cache-bad-entry/CMakeCache.txt
 create mode 100644 Tests/RunCMake/CommandLine/cache-empty-entry-result.txt
 create mode 100644 Tests/RunCMake/CommandLine/cache-empty-entry-stderr.txt
 create mode 100644 Tests/RunCMake/CommandLine/cache-empty-entry/CMakeCache.txt

diff --git a/Source/cmCacheManager.cxx b/Source/cmCacheManager.cxx
index ce8af55db..7466c299a 100644
--- a/Source/cmCacheManager.cxx
+++ b/Source/cmCacheManager.cxx
@@ -64,12 +64,14 @@ bool cmCacheManager::LoadCache(const std::string& path,
   const char *realbuffer;
   std::string buffer;
   std::string entryKey;
+  unsigned int lineno = 0;
   while(fin)
     {
     // Format is key:type=value
     std::string helpString;
     CacheEntry e;
     cmSystemTools::GetLineFromStream(fin, buffer);
+    lineno++;
     realbuffer = buffer.c_str();
     while(*realbuffer != '0' &&
           (*realbuffer == ' ' ||
@@ -77,6 +79,7 @@ bool cmCacheManager::LoadCache(const std::string& path,
            *realbuffer == '\r' ||
            *realbuffer == '\n'))
       {
+      if (*realbuffer == '\n') lineno++;
       realbuffer++;
       }
     // skip blank lines and comment lines
@@ -96,6 +99,7 @@ bool cmCacheManager::LoadCache(const std::string& path,
         helpString += &realbuffer[2];
         }
       cmSystemTools::GetLineFromStream(fin, buffer);
+      lineno++;
       realbuffer = buffer.c_str();
       if(!fin)
         {
@@ -138,8 +142,10 @@ bool cmCacheManager::LoadCache(const std::string& path,
       }
     else
       {
-      cmSystemTools::Error("Parse error in cache file ", cacheFile.c_str(),
-                           ". Offending entry: ", realbuffer);
+      std::ostringstream error;
+      error << "Parse error in cache file " << cacheFile;
+      error << " on line " << lineno << ". Offending entry: " << realbuffer;
+      cmSystemTools::Error(error.str().c_str());
       }
     }
   this->CacheMajorVersion = 0;
diff --git a/Tests/RunCMake/CommandLine/RunCMakeTest.cmake b/Tests/RunCMake/CommandLine/RunCMakeTest.cmake
index e77ba1f91..8068973a7 100644
--- a/Tests/RunCMake/CommandLine/RunCMakeTest.cmake
+++ b/Tests/RunCMake/CommandLine/RunCMakeTest.cmake
@@ -33,6 +33,11 @@ run_cmake_command(build-bad-dir
 run_cmake_command(build-bad-generator
   ${CMAKE_COMMAND} --build ${RunCMake_SOURCE_DIR}/cache-bad-generator)
 
+run_cmake_command(cache-bad-entry
+  ${CMAKE_COMMAND} --build ${RunCMake_SOURCE_DIR}/cache-bad-entry/)
+run_cmake_command(cache-empty-entry
+  ${CMAKE_COMMAND} --build ${RunCMake_SOURCE_DIR}/cache-empty-entry/)
+
 function(run_BuildDir)
   # Use a single build tree for a few tests without cleaning.
   set(RunCMake_TEST_BINARY_DIR ${RunCMake_BINARY_DIR}/BuildDir-build)
diff --git a/Tests/RunCMake/CommandLine/cache-bad-entry-result.txt b/Tests/RunCMake/CommandLine/cache-bad-entry-result.txt
new file mode 100644
index 000000000..d00491fd7
--- /dev/null
+++ b/Tests/RunCMake/CommandLine/cache-bad-entry-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/CommandLine/cache-bad-entry-stderr.txt b/Tests/RunCMake/CommandLine/cache-bad-entry-stderr.txt
new file mode 100644
index 000000000..150d2ca88
--- /dev/null
+++ b/Tests/RunCMake/CommandLine/cache-bad-entry-stderr.txt
@@ -0,0 +1 @@
+^CMake Error: Parse error in cache file .*/Tests/RunCMake/CommandLine/cache-bad-entry/CMakeCache.txt on line 7. Offending entry: BAD ENTRY.*
diff --git a/Tests/RunCMake/CommandLine/cache-bad-entry/CMakeCache.txt b/Tests/RunCMake/CommandLine/cache-bad-entry/CMakeCache.txt
new file mode 100644
index 000000000..75cd7c2e1
--- /dev/null
+++ b/Tests/RunCMake/CommandLine/cache-bad-entry/CMakeCache.txt
@@ -0,0 +1,10 @@
+# This is a comment
+
+// That was an empty line. This isn't.
+EMPTY_LINE:BOOL=FALSE
+
+// Uhoh! Here it comes
+BAD ENTRY
+
+// This is fine
+GOOD_ENTRY:BOOL=TRUE
diff --git a/Tests/RunCMake/CommandLine/cache-empty-entry-result.txt b/Tests/RunCMake/CommandLine/cache-empty-entry-result.txt
new file mode 100644
index 000000000..d00491fd7
--- /dev/null
+++ b/Tests/RunCMake/CommandLine/cache-empty-entry-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/CommandLine/cache-empty-entry-stderr.txt b/Tests/RunCMake/CommandLine/cache-empty-entry-stderr.txt
new file mode 100644
index 000000000..54f44525f
--- /dev/null
+++ b/Tests/RunCMake/CommandLine/cache-empty-entry-stderr.txt
@@ -0,0 +1 @@
+^CMake Error: Parse error in cache file .*/Tests/RunCMake/CommandLine/cache-empty-entry/CMakeCache.txt on line 5. Offending entry:.*
diff --git a/Tests/RunCMake/CommandLine/cache-empty-entry/CMakeCache.txt b/Tests/RunCMake/CommandLine/cache-empty-entry/CMakeCache.txt
new file mode 100644
index 000000000..44da1c9c3
--- /dev/null
+++ b/Tests/RunCMake/CommandLine/cache-empty-entry/CMakeCache.txt
@@ -0,0 +1,7 @@
+// This is valid
+VALID:BOOL=TRUE
+
+// This isn't
+
+// One final entry
+FINAL:BOOL=TRUE