Add convenience method for adding a patch

Signed-off-by: Nikola Forró <[email protected]>

Author: nforro

specfile/exceptions.py

@@ -33,3 +33,7 @@ class MacroOptionsException(SpecfileException):
 
 class DuplicateSourceException(SpecfileException):
     """Exception related to adding a duplicate source."""
+
+
+class SourceNumberException(SpecfileException):
+    """Exception related to source numbers."""

specfile/specfile.py

@@ -12,7 +12,7 @@
 import arrow
 
 from specfile.changelog import Changelog, ChangelogEntry
-from specfile.exceptions import SpecfileException
+from specfile.exceptions import SourceNumberException, SpecfileException
 from specfile.prep import Prep
 from specfile.rpm import RPM, Macros
 from specfile.sections import Sections
@@ -416,3 +416,39 @@ def set_version_and_release(self, version: str, release: str = "1") -> None:
         with self.tags() as tags:
             tags.version.value = version
             tags.release.value = self._get_updated_release(tags.release.value, release)
+
+    def add_patch(
+        self,
+        location: str,
+        number: Optional[int] = None,
+        comment: Optional[str] = None,
+        initial_number: int = 0,
+        number_digits: int = 4,
+    ) -> None:
+        """
+        Adds a patch.
+
+        Args:
+            location: Patch location (filename or URL).
+            number: Patch number. It will be auto-assigned if not specified.
+              If specified, it must be higher than any existing patch number.
+            comment: Associated comment.
+            initial_number: Auto-assigned number to start with if there are no patches.
+            number_digits: Number of digits in the patch number.
+
+        Raises:
+            SourceNumberException when the specified patch number is not higher
+              than any existing patch number.
+        """
+        with self.patches(default_source_number_digits=number_digits) as patches:
+            highest_number = max((p.number for p in patches), default=-1)
+            if number is not None:
+                if number <= highest_number:
+                    raise SourceNumberException(
+                        "Patch number must be higher than any existing patch number"
+                    )
+            else:
+                number = max(highest_number + 1, initial_number)
+            index = patches.insert_numbered(number, location)
+            if comment:
+                patches[index].comments.extend(comment.splitlines())

tests/integration/test_specfile.py

@@ -220,6 +220,33 @@ def test_set_version_and_release(spec_minimal, version, release):
     assert spec._spec.sourceHeader[rpm.RPMTAG_RELEASE] == spec.expanded_raw_release
 
 
+@pytest.mark.parametrize(
+    "location, number, comment",
+    [
+        ("patchX.patch", None, None),
+        ("patchX.patch", 0, None),
+        ("patch2.patch", None, None),
+        ("patch3.patch", 3, "patch3"),
+    ],
+)
+def test_add_patch(spec_autosetup, location, number, comment):
+    spec = Specfile(spec_autosetup)
+    if number == 0 or location == "patch2.patch":
+        with pytest.raises(SpecfileException):
+            spec.add_patch(location, number, comment)
+    else:
+        spec.add_patch(location, number, comment)
+        with spec.patches() as patches:
+            assert patches[-1].location == location
+            if number is not None:
+                assert patches[-1].number == number
+            else:
+                assert patches[-1].number == 3
+        with spec.sections() as sections:
+            if comment is not None:
+                assert sections.package[-4] == f"# {comment}"
+
+
 def test_remove_patches(spec_commented_patches):
     spec = Specfile(spec_commented_patches)
     with spec.patches() as patches: