fix: Parse URL sources that use the rename '#' tag

internal/rpm/spectool/spectool.go

@@ -13,12 +13,25 @@ import (
 
 // filenameFromURL attempts to parse value as a URL and extract the basename.
 // Returns the filename and true if value is a URL, or ("", false) if not.
+//
+// RPM specs use fragment conventions like "#/local-name" and "#./local-name"
+// to specify the local filename for URLs whose path doesn't contain a
+// meaningful basename (e.g., keyserver lookup URLs). When a fragment starting
+// with "/" or "./" is present, its basename is used instead of the URL path's
+// basename.
 func filenameFromURL(value string) (string, bool) {
 	parsed, err := url.Parse(value)
 	if err != nil || parsed.Scheme == "" || parsed.Host == "" {
 		return "", false
 	}
 
+	// RPM "#/filename" convention: fragment overrides the path basename.
+	// Variants: "#/name.asc" and "#./name.asc" both occur in the wild.
+	// Plain anchors like "#section" are not filename overrides.
+	if strings.HasPrefix(parsed.Fragment, "/") || strings.HasPrefix(parsed.Fragment, "./") {
+		return path.Base(parsed.Fragment), true
+	}
+
 	return path.Base(parsed.Path), true
 }
 

internal/rpm/spectool/spectool_test.go

@@ -73,6 +73,21 @@ func TestParseSpectoolOutput(t *testing.T) {
 			input:    "Source0: good.tar.gz\nPatch0: /bad/path\nPatch1: ok.patch",
 			expected: []string{"good.tar.gz", "ok.patch"},
 		},
+		{
+			name:     "URL with slash fragment extracts fragment basename",
+			input:    "Source0: https://example.com/lookup?q=abc#/local-name.asc",
+			expected: []string{"local-name.asc"},
+		},
+		{
+			name:     "URL with dot-slash fragment extracts fragment basename",
+			input:    "Source0: https://example.com/lookup?q=abc#./local-name.asc",
+			expected: []string{"local-name.asc"},
+		},
+		{
+			name:     "URL with fragment rename overrides path basename",
+			input:    "Patch0: https://example.com/pull/33.patch#/renamed.diff",
+			expected: []string{"renamed.diff"},
+		},
 	}
 
 	for _, testCase := range tests {
@@ -96,7 +111,9 @@ func TestFilenameFromURL(t *testing.T) {
 	}{
 		{"https URL", "https://example.com/file.tar.gz", "file.tar.gz", true},
 		{"URL with query", "https://example.com/file.tar.gz?raw=true", "file.tar.gz", true},
-		{"URL with fragment", "https://example.com/file.tar.gz#section", "file.tar.gz", true},
+		{"URL with non-path fragment", "https://example.com/file.tar.gz#section", "file.tar.gz", true},
+		{"RPM fragment slash", "https://example.com/lookup?q=abc#/local-name.asc", "local-name.asc", true},
+		{"RPM fragment dot-slash", "https://example.com/lookup?q=abc#./local-name.asc", "local-name.asc", true},
 		{"nested URL path", "https://example.com/a/b/c/file.tar.gz", "file.tar.gz", true},
 		{"ftp URL", "ftp://ftp.gnu.org/pub/gnu/sed/sed-4.9.tar.xz", "sed-4.9.tar.xz", true},
 		{"trailing slash", "https://example.com/", "/", true},