wip: misc project updates

src/pycalver/rewrite.py

@@ -1,4 +1,3 @@
-#!/usr/bin/env python
 # This file is part of the pycalver project
 # https://github.com/mbarkhau/pycalver
 #
@@ -15,42 +14,47 @@ from . import parse
 log = logging.getLogger("pycalver.rewrite")
 
 
-def rewrite(
-    new_version: str,
-    file_patterns: typ.Dict[str, typ.List[str]],
-    dry=False,
-    verbose=False,
-) -> None:
-    new_version_nfo = parse.parse_version_info(new_version)
+def rewrite_lines(
+    old_lines: typ.List[str], patterns: typ.List[str], new_version: str
+) -> typ.List[str]:
+    new_version_nfo        = parse.parse_version_info(new_version)
     new_version_fmt_kwargs = new_version_nfo._asdict()
 
-    matches: typ.List[parse.PatternMatch]
+    new_lines = old_lines.copy()
+
+    matches: typ.List[parse.PatternMatch] = parse.parse_patterns(old_lines, patterns)
+
+    for m in matches:
+        replacement = m.pattern.format(**new_version_fmt_kwargs)
+        span_l, span_r = m.span
+        new_line = m.line[:span_l] + replacement + m.line[span_r:]
+        new_lines[m.lineno] = new_line
+
+    return new_lines
+
+
+def rewrite(
+    new_version: str, file_patterns: typ.Dict[str, typ.List[str]], dry=False, verbose=False
+) -> None:
     for filepath, patterns in file_patterns.items():
         with io.open(filepath, mode="rt", encoding="utf-8") as fh:
             content = fh.read()
 
-        old_lines = content.splitlines()
-        new_lines = old_lines.copy()
+        # TODO (mb 2018-09-18): Detect line sep
+        line_sep = "\n"
 
-        matches = parse.parse_patterns(old_lines, patterns)
-        for m in matches:
-            replacement = m.pattern.format(**new_version_fmt_kwargs)
-            span_l, span_r = m.span
-            new_line = m.line[:span_l] + replacement + m.line[span_r:]
-            new_lines[m.lineno] = new_line
+        old_lines = content.splitlines()
+        new_lines = rewrite_lines(old_lines, patterns, new_version)
 
         if dry or verbose:
-            print("\n".join(difflib.unified_diff(
-                old_lines,
-                new_lines,
-                lineterm="",
-                fromfile="a/" + filepath,
-                tofile="b/" + filepath,
-            )))
+            diff_lines = difflib.unified_diff(
+                old_lines, new_lines, lineterm="", fromfile="a/" + filepath, tofile="b/" + filepath
+            )
+            print("\n".join(diff_lines))
 
         if dry:
             continue
 
-        new_content = "\n".join(new_lines)
+        new_content = line_sep.join(new_lines)
         with io.open(filepath, mode="wt", encoding="utf-8") as fh:
             fh.write(new_content)