WIP: refactoring and testing

src/pycalver/rewrite.py

@@ -5,17 +5,52 @@
 # (C) 2018 Manuel Barkhau (@mbarkhau)
 # SPDX-License-Identifier: MIT
 
-import logging
+import io
 import difflib
+import logging
+import typing as typ
+
+from . import parse
 
 log = logging.getLogger("pycalver.rewrite")
 
 
-def rewrite_file(file: str, pattern: str, dry=False) -> None:
-    difflib.unified_diff(
-        file_content_before.splitlines(),
-        file_content_after.splitlines(),
-        lineterm="",
-        fromfile="a/" + file,
-        tofile="b/" + file,
-    )
+def rewrite(
+    new_version: str,
+    file_patterns: typ.Dict[str, str],
+    dry=False,
+    verbose=False,
+) -> None:
+    new_version_nfo = parse.parse_version_info(new_version)
+    new_version_fmt_kwargs = new_version_nfo._asdict()
+
+    matches: typ.List[parse.PatternMatch]
+    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()
+
+        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
+
+        if dry or verbose:
+            print("\n".join(difflib.unified_diff(
+                old_lines,
+                new_lines,
+                lineterm="",
+                fromfile="a/" + filepath,
+                tofile="b/" + filepath,
+            )))
+
+        if dry:
+            continue
+
+        new_content = "\n".join(new_lines)
+        with io.open(filepath, mode="wt", encoding="utf-8") as fh:
+            fh.write(new_content)