feat(overlays): add spec-remove-section (#40)

Author: reubeno

docs/user/reference/config/overlays.md

@@ -22,6 +22,7 @@ These overlays modify `.spec` files using the structured spec parser, allowing p
 | `spec-prepend-lines` | Prepends lines to the start of a section; **fails if section doesn't exist** | `lines` |
 | `spec-append-lines` | Appends lines to the end of a section; **fails if section doesn't exist** | `lines` |
 | `spec-search-replace` | Regex-based search and replace on spec content | `regex` |
+| `spec-remove-section` | Removes an entire section from the spec; **fails if section doesn't exist** | `section` |
 | `patch-add` | Adds a patch file and registers it in the spec (PatchN tag or %patchlist) | `source` |
 | `patch-remove` | Removes patch files and their spec references matching a glob pattern | `file` |
 
@@ -53,7 +54,7 @@ successfully makes a replacement to at least one matching file.
 | Description | `description` | Human-readable explanation documenting the need for the change; helps identify overlays in error messages | All (optional) |
 | Tag | `tag` | The spec tag name (e.g., `BuildRequires`, `Requires`, `Version`) | `spec-add-tag`, `spec-insert-tag`, `spec-set-tag`, `spec-update-tag`, `spec-remove-tag` |
 | Value | `value` | The tag value to set, or value to match for removal | `spec-add-tag`, `spec-insert-tag`, `spec-set-tag`, `spec-update-tag`, `spec-remove-tag` (optional for matching) |
-| Section | `section` | The spec section to target (e.g., `%build`, `%install`, `%files`, `%description`) | `spec-prepend-lines`, `spec-append-lines`, `spec-search-replace` (optional) |
+| Section | `section` | The spec section to target (e.g., `%build`, `%install`, `%files`, `%description`) | `spec-prepend-lines`, `spec-append-lines`, `spec-search-replace` (optional), `spec-remove-section` |
 | Package | `package` | The sub-package name for multi-package specs; omit to target the main package | All spec overlays (optional) |
 | Regex | `regex` | Regular expression pattern to match | `spec-search-replace`, `file-search-replace` |
 | Replacement | `replacement` | Literal replacement text; capture group references like `$1` are **not** expanded. Omit or leave empty to delete matched text. | `spec-search-replace`, `file-search-replace`, `file-rename` |
@@ -272,6 +273,29 @@ description = "Remove CVE patches that are now upstream"
 > `PatchN` tags. Macro-based tag numbering (e.g., `Patch%{n}`) is not expanded and may
 > conflict with auto-assigned numbers.
 
+### Removing a Section
+
+The `spec-remove-section` overlay removes an entire section from the spec, including its
+header and all body lines. The section is identified by `section` name and optionally
+scoped to a specific sub-package with `package`.
+
+```toml
+[[components.mypackage.overlays]]
+type = "spec-remove-section"
+section = "%generate_buildrequires"
+description = "Remove dynamic build requirements generation"
+```
+
+To remove a section from a specific sub-package:
+
+```toml
+[[components.mypackage.overlays]]
+type = "spec-remove-section"
+section = "%files"
+package = "devel"
+description = "Remove devel sub-package files section"
+```
+
 ## Validation
 
 Overlay configurations are validated when the config file is loaded. Validation checks:

internal/app/azldev/core/sources/overlays.go

@@ -162,6 +162,11 @@ func ApplySpecOverlay(overlay projectconfig.ComponentOverlay, openedSpec *spec.S
 		if err != nil {
 			return fmt.Errorf("failed to search and replace in spec:\n%w", err)
 		}
+	case projectconfig.ComponentOverlayRemoveSection:
+		err := openedSpec.RemoveSection(overlay.SectionName, overlay.PackageName)
+		if err != nil {
+			return fmt.Errorf("failed to remove section from spec:\n%w", err)
+		}
 	case projectconfig.ComponentOverlayAddPatch:
 		destFilename := overlay.Filename
 		if destFilename == "" {

internal/app/azldev/core/sources/overlays_test.go

@@ -1177,3 +1177,72 @@ func TestApplyRemovePatchOverlay(t *testing.T) {
 		require.Error(t, err)
 	})
 }
+
+func TestApplyRemoveSectionOverlay(t *testing.T) {
+	t.Run("removes section from spec", func(t *testing.T) {
+		specContent := `Name: test
+Version: 1.0
+
+%generate_buildrequires
+%cargo_generate_buildrequires
+
+%build
+make
+`
+		overlay := projectconfig.ComponentOverlay{
+			Type:        projectconfig.ComponentOverlayRemoveSection,
+			SectionName: "%generate_buildrequires",
+		}
+
+		result, err := applyOverlayToSpecContents(t, overlay, specContent)
+		require.NoError(t, err)
+
+		assert.NotContains(t, result, "%generate_buildrequires")
+		assert.NotContains(t, result, "%cargo_generate_buildrequires")
+		assert.Contains(t, result, "%build")
+		assert.Contains(t, result, "make")
+	})
+
+	t.Run("removes section scoped by package", func(t *testing.T) {
+		specContent := `Name: test
+
+%files
+/usr/bin/test
+
+%files devel
+/usr/include/test.h
+
+%files libs
+/usr/lib/libtest.so
+`
+		overlay := projectconfig.ComponentOverlay{
+			Type:        projectconfig.ComponentOverlayRemoveSection,
+			SectionName: "%files",
+			PackageName: "devel",
+		}
+
+		result, err := applyOverlayToSpecContents(t, overlay, specContent)
+		require.NoError(t, err)
+
+		assert.Contains(t, result, "/usr/bin/test")
+		assert.NotContains(t, result, "/usr/include/test.h")
+		assert.Contains(t, result, "/usr/lib/libtest.so")
+	})
+
+	t.Run("fails when section does not exist", func(t *testing.T) {
+		specContent := `Name: test
+Version: 1.0
+
+%build
+make
+`
+		overlay := projectconfig.ComponentOverlay{
+			Type:        projectconfig.ComponentOverlayRemoveSection,
+			SectionName: "%check",
+		}
+
+		_, err := applyOverlayToSpecContents(t, overlay, specContent)
+		require.Error(t, err)
+		assert.Contains(t, err.Error(), "not found")
+	})
+}

internal/projectconfig/overlay.go

@@ -15,7 +15,7 @@ import (
 // ComponentOverlay represents an overlay that may be applied to a component's spec and/or its sources.
 type ComponentOverlay struct {
 	// The type of overlay to apply.
-	Type ComponentOverlayType `toml:"type" json:"type" validate:"required" jsonschema:"enum=spec-add-tag,enum=spec-insert-tag,enum=spec-set-tag,enum=spec-update-tag,enum=spec-remove-tag,enum=spec-prepend-lines,enum=spec-append-lines,enum=spec-search-replace,enum=patch-add,enum=patch-remove,enum=file-prepend-lines,enum=file-search-replace,enum=file-add,enum=file-remove,enum=file-rename,title=Overlay type,description=The type of overlay to apply"`
+	Type ComponentOverlayType `toml:"type" json:"type" validate:"required" jsonschema:"enum=spec-add-tag,enum=spec-insert-tag,enum=spec-set-tag,enum=spec-update-tag,enum=spec-remove-tag,enum=spec-prepend-lines,enum=spec-append-lines,enum=spec-search-replace,enum=spec-remove-section,enum=patch-add,enum=patch-remove,enum=file-prepend-lines,enum=file-search-replace,enum=file-add,enum=file-remove,enum=file-rename,title=Overlay type,description=The type of overlay to apply"`
 	// Human readable description of overlay; primarily present to document the need for the change.
 	Description string `toml:"description,omitempty" json:"description,omitempty" jsonschema:"title=Description,description=Human readable description of overlay"`
 
@@ -71,6 +71,7 @@ func (c *ComponentOverlay) ModifiesSpec() bool {
 		c.Type == ComponentOverlayPrependSpecLines ||
 		c.Type == ComponentOverlayAppendSpecLines ||
 		c.Type == ComponentOverlaySearchAndReplaceInSpec ||
+		c.Type == ComponentOverlayRemoveSection ||
 		c.Type == ComponentOverlayAddPatch ||
 		c.Type == ComponentOverlayRemovePatch
 }
@@ -113,6 +114,9 @@ const (
 	ComponentOverlayAppendSpecLines ComponentOverlayType = "spec-append-lines"
 	// ComponentOverlaySearchAndReplaceInSpec is an overlay that replaces text in a spec with other text.
 	ComponentOverlaySearchAndReplaceInSpec ComponentOverlayType = "spec-search-replace"
+	// ComponentOverlayRemoveSection is an overlay that removes an entire section from the spec;
+	// fails if the section doesn't exist.
+	ComponentOverlayRemoveSection ComponentOverlayType = "spec-remove-section"
 	// ComponentOverlayAddPatch is an overlay that adds a patch file and registers it in the spec.
 	// It copies the source file into the component sources and adds a PatchN tag (or appends to
 	// %%patchlist if one exists).
@@ -242,6 +246,10 @@ func (c *ComponentOverlay) Validate() error {
 		if err := requireFileBasename("replacement", c.Replacement); err != nil {
 			return err
 		}
+	case ComponentOverlayRemoveSection:
+		if c.SectionName == "" {
+			return missingField("section")
+		}
 	case ComponentOverlayAddPatch:
 		if c.Source == "" {
 			return missingField("source")

internal/projectconfig/overlay_test.go

@@ -359,6 +359,32 @@ func TestComponentOverlay_Validate(t *testing.T) {
 			errorExpected: true,
 			errorContains: "invalid glob pattern",
 		},
+		// spec-remove-section tests
+		{
+			name: "spec-remove-section valid with section only",
+			overlay: projectconfig.ComponentOverlay{
+				Type:        projectconfig.ComponentOverlayRemoveSection,
+				SectionName: "%generate_buildrequires",
+			},
+			errorExpected: false,
+		},
+		{
+			name: "spec-remove-section valid with section and package",
+			overlay: projectconfig.ComponentOverlay{
+				Type:        projectconfig.ComponentOverlayRemoveSection,
+				SectionName: "%files",
+				PackageName: "devel",
+			},
+			errorExpected: false,
+		},
+		{
+			name: "spec-remove-section missing section",
+			overlay: projectconfig.ComponentOverlay{
+				Type: projectconfig.ComponentOverlayRemoveSection,
+			},
+			errorExpected: true,
+			errorContains: "section",
+		},
 	}
 
 	for _, testCase := range testCases {
@@ -390,6 +416,7 @@ func TestComponentOverlay_ModifiesSpec(t *testing.T) {
 		projectconfig.ComponentOverlayPrependSpecLines,
 		projectconfig.ComponentOverlayAppendSpecLines,
 		projectconfig.ComponentOverlaySearchAndReplaceInSpec,
+		projectconfig.ComponentOverlayRemoveSection,
 		projectconfig.ComponentOverlayAddPatch,
 		projectconfig.ComponentOverlayRemovePatch,
 	}

internal/rpm/spec/edit.go

@@ -733,3 +733,56 @@ func (s *Spec) GetHighestPatchTagNumber() (int, error) {
 
 	return highest, err
 }
+
+// RemoveSection removes an entire section from the spec, including its header line and all
+// body lines. The section is identified by name and optional package qualifier. Returns
+// [ErrSectionNotFound] if the section doesn't exist.
+func (s *Spec) RemoveSection(sectionName, packageName string) error {
+	slog.Debug("Removing section from spec", "section", sectionName, "package", packageName)
+
+	if sectionName == "" {
+		return errors.New("cannot remove the global/preamble section")
+	}
+
+	// Find the start and end line numbers for the section.
+	startLine := -1
+	endLine := -1
+
+	err := s.Visit(func(ctx *Context) error {
+		if startLine >= 0 && endLine >= 0 {
+			// Already found the section boundaries.
+			return nil
+		}
+
+		if ctx.Target.TargetType == SectionStartTarget {
+			if ctx.CurrentSection.SectName == sectionName && ctx.CurrentSection.Package == packageName {
+				startLine = ctx.CurrentLineNum
+			}
+		}
+
+		if ctx.Target.TargetType == SectionEndTarget {
+			if ctx.CurrentSection.SectName == sectionName && ctx.CurrentSection.Package == packageName {
+				endLine = ctx.CurrentLineNum
+			}
+		}
+
+		return nil
+	})
+	if err != nil {
+		return fmt.Errorf("failed to scan spec for section %#q (package=%#q):\n%w", sectionName, packageName, err)
+	}
+
+	if startLine < 0 {
+		return fmt.Errorf("section %#q (package=%#q) not found:\n%w", sectionName, packageName, ErrSectionNotFound)
+	}
+
+	// endLine is the virtual end marker at the start of the next section (or EOF).
+	// We remove rawLines[startLine..endLine-1] inclusive.
+	if endLine < 0 {
+		endLine = len(s.rawLines)
+	}
+
+	s.RemoveLines(startLine, endLine)
+
+	return nil
+}