Make str() pretty-print the tree. Remove compose().

Author: Issac Trotts

README.md

@@ -15,7 +15,14 @@ or
 Usage
 -----
 
+The API can be used as follows:
+
     >>> import cmakelists_parsing.parsing as cmp
     >>> cmakelists_contents = 'FIND_PACKAGE(ITK REQUIRED)  # Hello, CMake!'
     >>> cmp.parse(cmakelists_contents)
     File([Command([u'ITK', u'REQUIRED', u'# Hello, CMake!'])])
+
+There is also a command line utility called cmake_pprint that pretty-prints
+CMake files:
+
+    $ cmake_pprint CMakeLists.txt

cmakelists_parsing/parsing.py

@@ -9,8 +9,20 @@
 _Arg = namedtuple('Arg', 'contents comments')
 _Command = namedtuple('Command', 'name body comment')
 BlankLine = namedtuple('BlankLine', '')
-File = namedtuple('File', 'contents')
-# TODO: if, else, endif, function, endfunction, macro, endmacro
+
+class File(list):
+    """Top node of the syntax tree for a CMakeLists file."""
+
+    def __str__(self):
+        '''
+        Returns the pretty-print string for tree
+        with indentation given by the string tab.
+        '''
+        return '\n'.join(compose_lines(self)) + '\n'
+
+    def __repr__(self):
+        return 'File(' + repr(list(self)) + ')'
+
 class Comment(str):
     def __repr__(self):
         return 'Comment(' + str(self) + ')'
@@ -24,6 +36,9 @@ def Command(name, body, comment=None):
 class CMakeParseError(Exception):
     pass
 
+def prettify(s):
+    return str(parse(s))
+
 def parse(s, path='<string>'):
     '''
     Parses a string s in CMakeLists format whose
@@ -37,19 +52,13 @@ def parse(s, path='<string>'):
     return File(items)
 
 def strip_blanks(tree):
-    return File([x for x in tree.contents if not isinstance(x, BlankLine)])
+    return File([x for x in tree if not isinstance(x, BlankLine)])
 
-def compose(tree, tab='    '):
-    '''
-    Returns the pretty-print string for tree
-    with indentation given by the string tab.
-    '''
-    return '\n'.join(compose_lines(tree.contents, tab)) + '\n'
-
-def compose_lines(tree_contents, tab):
+def compose_lines(tree_contents):
     """
     Yields pretty-printed lines of a CMakeLists file.
     """
+    tab = '    '
     level = 0
     for item in tree_contents:
         if isinstance(item, (Comment, str)):
@@ -164,6 +173,7 @@ def tokenize(s):
         line_num += tok_contents.count('\n')
 
 def main():
+    # Parse arguments
     import argparse
     import sys
     parser = argparse.ArgumentParser(description='Pretty-print CMakeLists files.')
@@ -172,18 +182,24 @@ def main():
     parser.add_argument('-t', '--tree', action='store_true',
                         help='print out the syntax trees')
     args = parser.parse_args()
+
+    # Gather files
     filenames = args.files
-    files = (open(f) for f in filenames) if filenames else [sys.stdin]
-    for f in files:
-        with f:
-            input = f.read()
-            tree = parse(input)
+    files = [('<stdin>', sys.stdin)]
+    if filenames:
+        files = [(name, open(name)) for name in filenames]
+
+    # Process files
+    for (name, file) in files:
+        with file:
+            input = file.read()
+            tree = parse(input, path=name)
             if args.tree:
                 # Print out AST
-                print(str(tree))
+                print(repr(tree))
             else:
                 # Pretty print
-                print(compose(tree), end='')
+                print(str(tree), end='')
 
 if __name__ == '__main__':
     main()

example_inputs/macro.txt

@@ -4,7 +4,3 @@ macro(hello MESSAGE)
 endmacro(hello) 
 # call the macro with the string "hello world" 
 hello("hello world") 
-# define a function hello 
-function(hello MESSAGE)
-    message(${MESSAGE}) 
-endfunction(hello)

tests/example_inputs_test.py

@@ -14,7 +14,7 @@ def yield_examples():
 
 class ExamplesTestCase(unittest.TestCase):
     def test_idempotency_of_parse_unparse(self):
-        round_trip = lambda s, path='<string>': cmp.compose(cmp.parse(s, path))
+        round_trip = lambda s, path='<string>': str(cmp.parse(s, path))
         for path, contents in yield_examples():
             self.assertEqual(round_trip(contents, path),
                              round_trip(round_trip(contents, path)),
@@ -23,6 +23,6 @@ def test_idempotency_of_parse_unparse(self):
     def test_tree_is_unchanged(self):
         for path, contents in yield_examples():
             expected = cmp.parse(contents, path)
-            actual = cmp.parse(cmp.compose(cmp.parse(contents, path)))
+            actual = cmp.parse(str(cmp.parse(contents, path)))
             msg = 'Failed on %s.\nExpected\n%s\n\nGot\n%s' % (path, expected, actual)
             self.assertEqual(expected, actual, msg)

tests/parsing_test.py

@@ -3,7 +3,7 @@
 import unittest
 
 from cmakelists_parsing.parsing import (
-    File, Command, Comment, BlankLine, Arg, parse, compose)
+    File, Command, Comment, BlankLine, Arg, parse, prettify)
 
 class ParsingTestCase(unittest.TestCase):
     def setUp(self):
@@ -55,7 +55,7 @@ def test_idempotency_of_parsing_and_unparsing(self):
 FIND_PACKAGE(ITK REQUIRED)
 INCLUDE(${ITK_USE_FILE})
 '''
-        round_trip = lambda s: compose(parse(s))
+        round_trip = lambda s: str(parse(s))
         self.assertEqual(round_trip(input), round_trip(round_trip(input)))
 
     def test_invalid_format_raises_an_exception(self):
@@ -97,7 +97,7 @@ def test_arg_comments_preserved(self):
     x  # inline comment about x
     )
 '''
-        output = compose(parse(input))
+        output = str(parse(input))
 
     def test_comments_preserved(self):
         input = '''\
@@ -111,7 +111,7 @@ def test_comments_preserved(self):
     "y"  # inline comment about a quoted string "y"
     )  # inline comment for Command2
 '''
-        output = compose(parse(input))
+        output = str(parse(input))
 
         self.assertMultiLineEqual(input, output)
 
@@ -141,7 +141,19 @@ def test_ifs_indented(self):
     endif(c)
 endif(a)
 '''
-        self.assertMultiLineEqual(input, compose(parse(input)))
+        self.assertMultiLineEqual(input, str(parse(input)))
+
+    def test_functions_indented(self):
+        input = '''
+macro(hello MESSAGE)
+    message(${MESSAGE})
+endmacro(hello)  # call the macro with the string "hello world"
+hello("hello world")
+'''
+        self.assertUnchangedByPrettyPrinting(input)
+
+    def assertUnchangedByPrettyPrinting(self, input):
+        self.assertMultiLineEqual(input, prettify(input))
 
 if __name__ == '__main__':
     unittest.main()