[clang-rename] add basic vim integration

This patch introduces basic Vim integration for clang-rename tool.

For setup reference see clang-rename/tool/clang-rename.py

Patch by Kirill Bobyrev!

Differential revision: http://reviews.llvm.org/D22087

llvm-svn: 274759

clang-tools-extra/clang-rename/tool/clang-rename.py

@@ -0,0 +1,61 @@
+'''
+Minimal clang-rename integration with Vim.
+
+Before installing make sure one of the following is satisfied:
+
+* clang-rename is in your PATH
+* `g:clang_rename_path` in ~/.vimrc points to valid clang-rename executable
+* `binary` in clang-rename.py points to valid to clang-rename executable
+
+To install, simply put this into your ~/.vimrc
+
+    map ,cr :pyf <path-to>/clang-rename.py<cr>
+
+IMPORTANT NOTE: Before running the tool, make sure you saved the file.
+
+All you have to do now is to place a cursor on a variable/function/class which
+you would like to rename and press ',cr'. You will be promted a new name if the
+cursor points to a valid symbol.
+'''
+
+import vim
+import subprocess
+import sys
+
+def main():
+    binary = 'clang-rename'
+    if vim.eval('exists("g:clang_rename_path")') == "1":
+        binary = vim.eval('g:clang_rename')
+
+    # Get arguments for clang-rename binary.
+    offset = int(vim.eval('line2byte(line("."))+col(".")')) - 2
+    if offset < 0:
+        print >> sys.stderr, '''Couldn\'t determine cursor position.
+                                Is your file empty?'''
+        return
+    filename = vim.current.buffer.name
+
+    new_name_request_message = 'type new name:'
+    new_name = vim.eval("input('{}\n')".format(new_name_request_message))
+
+    # Call clang-rename.
+    command = [binary,
+               filename,
+               '-i',
+               '-offset', str(offset),
+               '-new-name', str(new_name)]
+    # FIXME: make it possible to run the tool on unsaved file.
+    p = subprocess.Popen(command,
+                         stdout=subprocess.PIPE,
+                         stderr=subprocess.PIPE)
+    stdout, stderr = p.communicate()
+
+    if stderr:
+        print stderr
+
+    # Reload all buffers in Vim.
+    vim.command("bufdo edit")
+
+
+if __name__ == '__main__':
+    main()