Fixes #116

This patch changes hashin such that,

If the package specified has underscores in its name, but the new package
has hyphens, the following occurs

* If there is a new version, hashin updates the package in requirements to
  be the hyphenated name
* If there is no new version, the underscored name remains in place

Prior to this patch, the 1st case about would not occur. Instead, hashin
would append the new version in its hyphenated form to the requirements file
and leave the old version in its underscored form in the requirements file.

Author: caphrim007

hashin.py

@@ -388,17 +388,39 @@ def amend_requirements_content(requirements, all_new_lines):
     padding = " " * 4
 
     def is_different_lines(old_lines, new_lines, indent):
+        # This regex is used to only temporarily normalize the names of packages
+        # in the lines being compared. This results in "old" names matching
+        # "new" names so that hashin correctly replaces them when it looks for
+        # them.
+        rex = re.compile("[-_]")
+
         # This assumes that the package is already mentioned in the old
         # requirements. Now we just need to double-check that its lines are
         # different.
         # The 'new_lines` is what we might intend to replace it with.
-        old = set([l.strip(" \\") for l in old_lines])
+        old = set([rex.sub("-", l.strip(" \\")) for l in old_lines])
         new = set([indent + x.strip(" \\") for x in new_lines])
         return old != new
 
     for package, old_name, new_text in all_new_lines:
+        # The call to `escape` will turn hyphens into escaped hyphens
+        #
+        # ex.
+        #   -       becomes     \\-
+        #
+        escaped = re.escape(old_name)
+
+        # This changes those escaped hypens into a pattern to match
+        #
+        # ex.
+        #   \\-     becomes     [-_]
+        #
+        # This is necessary so that hashin will correctly find underscored (old)
+        # and hyphenated (new) package names so that it will correctly replace an
+        # old name with the new name when there is a version update.
+        escape_replaced = escaped.replace("\\-", "[-_]")
         regex = re.compile(
-            r"^(?P<indent>[ \t]*){0}(\[.*\])?==".format(re.escape(old_name)),
+            r"^(?P<indent>[ \t]*){0}(\[.*\])?==".format(escape_replaced),
             re.IGNORECASE | re.MULTILINE,
         )
         # if the package wasn't already there, add it to the bottom

tests/test_cli.py

@@ -294,6 +294,26 @@ def test_amend_requirements_content_new():
     assert result == requirements + new_lines[2]
 
 
+def test_amend_requirements_content_new_2():
+    requirements = (
+        """
+# empty so far
+    """.strip()
+        + "\n"
+    )
+    new_lines = (
+        "discogs-client",
+        "Discogs_client",
+        """
+discogs-client==1.1 \\
+    --hash=sha256:4d64ed1b9e0e73095f5cfa87f0e97ddb4c840049e8efeb7e63b46118ba1d623a
+    """.strip()
+        + "\n",
+    )
+    result = hashin.amend_requirements_content(requirements, [new_lines])
+    assert result == requirements + new_lines[2]
+
+
 def test_amend_requirements_different_old_name():
     requirements = (
         """
@@ -2665,3 +2685,222 @@ def mock_input(question):
             "hashin", old_version, new_version, force_yes=True
         )
         assert result == "YES"
+
+
+class TestIssue116:
+    """Tests for validating fix related to GH issue #116
+
+    https://github.com/peterbe/hashin/issues/116
+    """
+
+    def test_amend_requirements_content_new_without_env_markers(self):
+        requirements = (
+            """
+# empty so far
+        """.strip()
+            + "\n"
+        )
+        new_lines = (
+            "discogs-client",
+            "discogs-client",
+            """
+discogs-client==1.1 \\
+    --hash=sha256:4d64ed1b9e0e73095f5cfa87f0e97ddb4c840049e8efeb7e63b46118ba1d623a
+        """.strip()
+            + "\n",
+        )
+        result = hashin.amend_requirements_content(requirements, [new_lines])
+        assert result == requirements + new_lines[2]
+
+    def test_amend_requirements_content_new_with_env_markers(self):
+        requirements = (
+            """
+# empty so far
+        """.strip()
+            + "\n"
+        )
+        new_lines = (
+            "discogs-client; python_version <= '3.4'",
+            "discogs-client; python_version <= '3.4'",
+            """
+discogs-client==1.1; python_version <= '3.4' \\
+    --hash=sha256:4d64ed1b9e0e73095f5cfa87f0e97ddb4c840049e8efeb7e63b46118ba1d623a
+        """.strip()
+            + "\n",
+        )
+        result = hashin.amend_requirements_content(requirements, [new_lines])
+        assert result == requirements + new_lines[2]
+
+    def test_amend_requirements_different_old_name_without_env_markers(self):
+        requirements = (
+            """
+readme_renderer==25.0 \\
+    --hash=sha256:1b6d8dd1673a0b293766b4106af766b6eff3654605f9c4f239e65de6076bc222 \\
+    --hash=sha256:e67d64242f0174a63c3b727801a2fff4c1f38ebe5d71d95ff7ece081945a6cd4
+
+        """.strip()
+            + "\n"
+        )
+
+        new_lines = (
+            "readme-renderer",
+            "readme-renderer",
+            """
+readme-renderer==26.0 \\
+    --hash=sha256:cbe9db71defedd2428a1589cdc545f9bd98e59297449f69d721ef8f1cfced68d \\
+    --hash=sha256:cc4957a803106e820d05d14f71033092537a22daa4f406dfbdd61177e0936376
+
+        """.strip()
+            + "\n",
+        )
+        result = hashin.amend_requirements_content(requirements, [new_lines])
+        assert result == new_lines[2]
+
+    def test_amend_requirements_different_old_name_with_env_markers(self):
+        requirements = (
+            """
+readme_renderer==25.0; python_version <= "3.4" \\
+    --hash=sha256:1b6d8dd1673a0b293766b4106af766b6eff3654605f9c4f239e65de6076bc222 \\
+    --hash=sha256:e67d64242f0174a63c3b727801a2fff4c1f38ebe5d71d95ff7ece081945a6cd4
+
+        """.strip()
+            + "\n"
+        )
+
+        new_lines = (
+            "readme-renderer",
+            "readme-renderer",
+            """
+readme-renderer==26.0; python_version <= "3.4" \\
+    --hash=sha256:cbe9db71defedd2428a1589cdc545f9bd98e59297449f69d721ef8f1cfced68d \\
+    --hash=sha256:cc4957a803106e820d05d14f71033092537a22daa4f406dfbdd61177e0936376
+
+        """.strip()
+            + "\n",
+        )
+        result = hashin.amend_requirements_content(requirements, [new_lines])
+        assert result == new_lines[2]
+
+    def test_amend_requirements_without_env_markers_same_version(self):
+        requirements = (
+            """
+readme_renderer==25.0 \\
+    --hash=sha256:1b6d8dd1673a0b293766b4106af766b6eff3654605f9c4f239e65de6076bc222 \\
+    --hash=sha256:e67d64242f0174a63c3b727801a2fff4c1f38ebe5d71d95ff7ece081945a6cd4
+
+        """.strip()
+            + "\n"
+        )
+
+        new_lines = (
+            "readme-renderer",
+            "readme-renderer",
+            """
+readme_renderer==25.0 \\
+    --hash=sha256:1b6d8dd1673a0b293766b4106af766b6eff3654605f9c4f239e65de6076bc222 \\
+    --hash=sha256:e67d64242f0174a63c3b727801a2fff4c1f38ebe5d71d95ff7ece081945a6cd4
+
+        """.strip()
+            + "\n",
+        )
+        result = hashin.amend_requirements_content(requirements, [new_lines])
+        assert result == requirements
+
+    def test_amend_requirements_with_env_markers_same_version(self):
+        requirements = (
+            """
+readme_renderer==25.0; python_version <= "3.4" \\
+    --hash=sha256:1b6d8dd1673a0b293766b4106af766b6eff3654605f9c4f239e65de6076bc222 \\
+    --hash=sha256:e67d64242f0174a63c3b727801a2fff4c1f38ebe5d71d95ff7ece081945a6cd4
+
+        """.strip()
+            + "\n"
+        )
+
+        new_lines = (
+            "readme-renderer",
+            "readme-renderer",
+            """
+readme_renderer==25.0; python_version <= "3.4" \\
+    --hash=sha256:1b6d8dd1673a0b293766b4106af766b6eff3654605f9c4f239e65de6076bc222 \\
+    --hash=sha256:e67d64242f0174a63c3b727801a2fff4c1f38ebe5d71d95ff7ece081945a6cd4
+
+        """.strip()
+            + "\n",
+        )
+        result = hashin.amend_requirements_content(requirements, [new_lines])
+        assert result == requirements
+
+    def test_run_old_name_no_version_change(self, murlopen, tmpfile, capsys):
+        def mocked_get(url, **options):
+            if url == "https://pypi.org/pypi/readme_renderer/json":
+                return _Response(
+                    {
+                        "info": {"version": "0.25", "name": "readme-renderer"},
+                        "releases": {
+                            "25.0": [
+                                {
+                                    "url": "https://pypi.org/packages/source/p/readme-renderer/readme_renderer-25.0.tar.gz",
+                                    "digests": {"sha256": "bbbbb"},
+                                }
+                            ],
+                            "26.0": [
+                                {
+                                    "url": "https://pypi.org/packages/source/p/readme-renderer/readme_renderer-26.0.tar.gz",
+                                    "digests": {"sha256": "aaaaa"},
+                                }
+                            ],
+                        },
+                    }
+                )
+
+        murlopen.side_effect = mocked_get
+
+        with tmpfile() as filename:
+            with open(filename, "w") as f:
+                f.write("readme_renderer==25.0 \\\n")
+                f.write("    --hash=sha256:bbbbb\n")
+                f.write("\n")
+
+            retcode = hashin.run("readme_renderer==25.0", filename, "sha256")
+            assert retcode == 0
+            with open(filename) as f:
+                output = f.read()
+            assert "readme_renderer==25.0" in output
+
+    def test_run_old_name_new_version_change(self, murlopen, tmpfile, capsys):
+        def mocked_get(url, **options):
+            if url == "https://pypi.org/pypi/readme_renderer/json":
+                return _Response(
+                    {
+                        "info": {"version": "0.25", "name": "readme-renderer"},
+                        "releases": {
+                            "25.0": [
+                                {
+                                    "url": "https://pypi.org/packages/source/p/readme-renderer/readme_renderer-25.0.tar.gz",
+                                    "digests": {"sha256": "bbbbb"},
+                                }
+                            ],
+                            "26.0": [
+                                {
+                                    "url": "https://pypi.org/packages/source/p/readme-renderer/readme_renderer-26.0.tar.gz",
+                                    "digests": {"sha256": "aaaaa"},
+                                }
+                            ],
+                        },
+                    }
+                )
+
+        murlopen.side_effect = mocked_get
+
+        with tmpfile() as filename:
+            with open(filename, "w") as f:
+                f.write("readme_renderer==26.0 \\\n")
+                f.write("    --hash=sha256:bbbbb\n")
+                f.write("\n")
+
+            retcode = hashin.run("readme_renderer==26.0", filename, "sha256")
+            assert retcode == 0
+            with open(filename) as f:
+                output = f.read()
+            assert "readme-renderer==26.0" in output

tox.ini

@@ -7,6 +7,7 @@ python =
   3.4: py34
   3.5: py35
   3.6: py36, lint, restlint
+  3.7: py37, lint, restlint
 
 [testenv]
 usedevelop = True