Move, rename, and document Visual Studio GN helper script

BUG=skia:

DOCS_PREVIEW= https://skia.org/?cl=5983

Change-Id: I32ac2c5275eb86adaa2be9ceee061b2956db70ad
Reviewed-on: https://skia-review.googlesource.com/5983
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Hal Canary <halcanary@google.com>

1 files changed, 164 insertions, 0 deletions

diff --git a/gn/gn_meta_sln.py b/gn/gn_meta_sln.py
new file mode 100644
index 0000000000..2cb4ae59ae
--- /dev/null
+++ b/gn/gn_meta_sln.py
@@ -0,0 +1,164 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import os
+import glob
+import re
+import sys
+from shutil import copyfile
+
+# Helpers
+def ensureExists(path):
+    try:
+        os.makedirs(path)
+    except OSError:
+        pass
+
+def writeLinesToFile(lines, fileName):
+    ensureExists(os.path.dirname(fileName))
+    with open(fileName, "w") as f:
+        f.writelines(lines)
+
+def extractIdg(projFileName):
+    result = []
+    with open(projFileName) as projFile:
+        lines = iter(projFile)
+        for pLine in lines:
+            if "<ItemDefinitionGroup" in pLine:
+                while not "</ItemDefinitionGroup" in pLine:
+                    result.append(pLine)
+                    pLine = lines.next()
+                result.append(pLine)
+                return result
+
+# [ (name, hasSln), ... ]
+configs = []
+
+# Find all directories that can be used as configs (and record if they have VS
+# files present)
+for root, dirs, files in os.walk("out"):
+    for outDir in dirs:
+        gnFile = os.path.join("out", outDir, "build.ninja.d")
+        if os.path.exists(gnFile):
+            slnFile = os.path.join("out", outDir, "all.sln")
+            configs.append((outDir, os.path.exists(slnFile)))
+    break
+
+# Every project has a GUID that encodes the type. We only care about C++.
+cppTypeGuid = "8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942"
+
+# name -> [ (config, pathToProject, GUID), ... ]
+allProjects = {}
+projectPattern = (r'Project\("\{' + cppTypeGuid +
+                  r'\}"\) = "([^"]*)", "([^"]*)", "\{([^\}]*)\}"')
+
+for config in configs:
+    if config[1]:
+        slnLines = iter(open("out/" + config[0] + "/all.sln"))
+        for slnLine in slnLines:
+            matchObj = re.match(projectPattern, slnLine)
+            if matchObj:
+                projName = matchObj.group(1)
+                if not allProjects.has_key(projName):
+                    allProjects[projName] = []
+                allProjects[projName].append((config[0], matchObj.group(2),
+                                              matchObj.group(3)))
+
+# We need something to work with. Typically, this will fail if no GN folders
+# have IDE files
+if len(allProjects) == 0:
+    print "ERROR: At least one GN directory must have been built with --ide=vs"
+    sys.exit()
+
+# Create a new solution. We arbitrarily use the first config as the GUID source
+# (but we need to match that behavior later, when we copy/generate the project
+# files).
+newSlnLines = []
+newSlnLines.append(
+    'Microsoft Visual Studio Solution File, Format Version 12.00\n')
+newSlnLines.append('# Visual Studio 2015\n')
+for projName, projConfigs in allProjects.items():
+    newSlnLines.append('Project("{' + cppTypeGuid + '}") = "' + projName +
+                       '", "' + projConfigs[0][1] + '", "{' + projConfigs[0][2]
+                       + '}"\n')
+    newSlnLines.append('EndProject\n')
+
+newSlnLines.append('Global\n')
+newSlnLines.append(
+    '\tGlobalSection(SolutionConfigurationPlatforms) = preSolution\n')
+for config in configs:
+    newSlnLines.append('\t\t' + config[0] + '|x64 = ' + config[0] + '|x64\n')
+newSlnLines.append('\tEndGlobalSection\n')
+newSlnLines.append(
+    '\tGlobalSection(ProjectConfigurationPlatforms) = postSolution\n')
+for projName, projConfigs in allProjects.items():
+    projGuid = projConfigs[0][2]
+    for config in configs:
+        newSlnLines.append('\t\t{' + projGuid + '}.' + config[0] +
+                           '|x64.ActiveCfg = ' + config[0] + '|x64\n')
+        newSlnLines.append('\t\t{' + projGuid + '}.' + config[0] +
+                           '|x64.Build.0 = ' + config[0] + '|x64\n')
+newSlnLines.append('\tEndGlobalSection\n')
+newSlnLines.append('\tGlobalSection(SolutionProperties) = preSolution\n')
+newSlnLines.append('\t\tHideSolutionNode = FALSE\n')
+newSlnLines.append('\tEndGlobalSection\n')
+newSlnLines.append('\tGlobalSection(NestedProjects) = preSolution\n')
+newSlnLines.append('\tEndGlobalSection\n')
+newSlnLines.append('EndGlobal\n')
+
+# Write solution file
+writeLinesToFile(newSlnLines, "out/sln/skia.sln")
+
+idgHdr = "<ItemDefinitionGroup Condition=\"'$(Configuration)|$(Platform)'=='"
+
+# Now, bring over the project files
+for projName, projConfigs in allProjects.items():
+    # Paths to project and filter file in src and dst locations
+    srcProjPath = os.path.join("out", projConfigs[0][0], projConfigs[0][1])
+    dstProjPath = os.path.join("out", "sln", projConfigs[0][1])
+    srcFilterPath = srcProjPath + ".filters"
+    dstFilterPath = dstProjPath + ".filters"
+
+    # Copy the filter file unmodified
+    ensureExists(os.path.dirname(dstProjPath))
+    copyfile(srcFilterPath, dstFilterPath)
+
+    # Bring over the project file, modified with extra configs
+    with open(srcProjPath) as srcProjFile:
+        projLines = iter(srcProjFile)
+        newProjLines = []
+        for line in projLines:
+            if "<ItemDefinitionGroup" in line:
+                # This is a large group that contains many settings. We need to
+                # replicate it, with conditions so it varies per configuration.
+                idgLines = []
+                while not "</ItemDefinitionGroup" in line:
+                    idgLines.append(line)
+                    line = projLines.next()
+                idgLines.append(line)
+                for projConfig in projConfigs:
+                    configIdgLines = extractIdg(os.path.join("out",
+                                                             projConfig[0],
+                                                             projConfig[1]))
+                    newProjLines.append(idgHdr + projConfig[0] + "|x64'\">\n")
+                    for idgLine in configIdgLines[1:]:
+                        newProjLines.append(idgLine)
+            elif "ProjectConfigurations" in line:
+                newProjLines.append(line)
+                projConfigLines = [
+                    projLines.next(),
+                    projLines.next(),
+                    projLines.next(),
+                    projLines.next() ]
+                for config in configs:
+                    for projConfigLine in projConfigLines:
+                        newProjLines.append(projConfigLine.replace("GN",
+                                                                   config[0]))
+            elif "<OutDir" in line:
+                newProjLines.append(line.replace(projConfigs[0][0],
+                                                 "$(Configuration)"))
+            else:
+                newProjLines.append(line)
+        with open(dstProjPath, "w") as newProj:
+            newProj.writelines(newProjLines)