introduced option to specify file encoding

pytest_doctestplus/plugin.py

@@ -111,6 +111,10 @@ def pytest_addoption(parser):
                          "Options accepted are 'txt', 'tex', and 'rst'. "
                          "This is no longer recommended, use --doctest-glob instead."
                      ))
+
+    parser.addoption("--text-file-encoding", action="store",
+                     help="Specify encoding for files.",
+                     default="utf-8")
 
     # Defaults to `atol` parameter from `numpy.allclose`.
     parser.addoption("--doctest-plus-atol", action="store",
@@ -142,6 +146,9 @@ def pytest_addoption(parser):
     parser.addini("text_file_format",
                   "Default format for docs. "
                   "This is no longer recommended, use --doctest-glob instead.")
+
+    parser.addini("text_file_encoding",
+                  "Default encoding for text files.", default=None)
 
     parser.addini("doctest_optionflags", "option flags for doctests",
                   type="args", default=["ELLIPSIS", "NORMALIZE_WHITESPACE"],)
@@ -912,13 +919,13 @@ def test_filter(test):
         return tests
 
 
-def write_modified_file(fname, new_fname, changes):
+def write_modified_file(fname, new_fname, changes, encoding=None):
     # Sort in reversed order to edit the lines:
     bad_tests = []
     changes.sort(key=lambda x: (x["test_lineno"], x["example_lineno"]),
                  reverse=True)
 
-    with open(fname) as f:
+    with open(fname, encoding=encoding) as f:
         text = f.readlines()
 
     for change in changes:
@@ -939,7 +946,7 @@ def write_modified_file(fname, new_fname, changes):
 
         text[lineno:lineno+want.count("\n")] = [got]
 
-    with open(new_fname, "w") as f:
+    with open(new_fname, "w", encoding=encoding) as f:
         f.write("".join(text))
 
     return bad_tests
@@ -953,6 +960,9 @@ def pytest_terminal_summary(terminalreporter, exitstatus, config):
     all_bad_tests = []
     if not diff_mode:
         return  # we do not report or apply diffs
+
+    # get encoding to open file default ini=None or option="utf-8"
+    encoding = config.getini("text_file_encoding") or config.getoption("text_file_encoding")
 
     if diff_mode != "overwrite":
         # In this mode, we write a corrected file to a temporary folder in
@@ -974,7 +984,7 @@ def pytest_terminal_summary(terminalreporter, exitstatus, config):
                 new_fname = fname.replace(common_path, tmpdirname)
                 os.makedirs(os.path.split(new_fname)[0], exist_ok=True)
 
-                bad_tests = write_modified_file(fname, new_fname, changes)
+                bad_tests = write_modified_file(fname, new_fname, changes, encoding)
                 all_bad_tests.extend(bad_tests)
 
                 # git diff returns 1 to signal changes, so just ignore the
@@ -1013,7 +1023,7 @@ def pytest_terminal_summary(terminalreporter, exitstatus, config):
             return
         terminalreporter.write_line("Applied fix to the following files:")
         for fname, changes in changesets.items():
-            bad_tests = write_modified_file(fname, fname, changes)
+            bad_tests = write_modified_file(fname, fname, changes, encoding)
             all_bad_tests.extend(bad_tests)
             terminalreporter.write_line(f"    {fname}")