Add codemod to migrate expires integer values to day-string format

pkg/cli/codemod_expires_integer.go

@@ -0,0 +1,145 @@
+package cli
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+
+	"github.com/github/gh-aw/pkg/logger"
+)
+
+var expiresIntegerCodemodLog = logger.New("cli:codemod_expires_integer")
+
+// expiresIntegerValuePattern matches an expires value that is a pure integer (possibly with a trailing comment)
+var expiresIntegerValuePattern = regexp.MustCompile(`^(\s*)(\d+)(\s*)(#.*)?$`)
+
+// getExpiresIntegerToStringCodemod creates a codemod for converting integer expires values to day strings.
+// Converts e.g. "expires: 7" to "expires: 7d" in all safe-outputs types.
+func getExpiresIntegerToStringCodemod() Codemod {
+	return Codemod{
+		ID:           "expires-integer-to-string",
+		Name:         "Convert expires integer to day string",
+		Description:  "Converts integer 'expires' values (e.g., 'expires: 7') to day string format (e.g., 'expires: 7d') in safe-outputs types",
+		IntroducedIn: "0.13.0",
+		Apply: func(content string, frontmatter map[string]any) (string, bool, error) {
+			// Check if safe-outputs exists
+			safeOutputsValue, hasSafeOutputs := frontmatter["safe-outputs"]
+			if !hasSafeOutputs {
+				return content, false, nil
+			}
+
+			safeOutputsMap, ok := safeOutputsValue.(map[string]any)
+			if !ok {
+				return content, false, nil
+			}
+
+			// Check if any safe-outputs type has an integer expires value
+			hasIntegerExpires := false
+			for _, outputTypeValue := range safeOutputsMap {
+				outputTypeMap, ok := outputTypeValue.(map[string]any)
+				if !ok {
+					continue
+				}
+				if expiresValue, hasExpires := outputTypeMap["expires"]; hasExpires {
+					switch expiresValue.(type) {
+					case int, int64, uint64:
+						hasIntegerExpires = true
+					}
+				}
+			}
+
+			if !hasIntegerExpires {
+				return content, false, nil
+			}
+
+			// Parse frontmatter to get raw lines
+			frontmatterLines, markdown, err := parseFrontmatterLines(content)
+			if err != nil {
+				return content, false, err
+			}
+
+			// Convert integer expires values to day strings within safe-outputs blocks
+			result, modified := convertExpiresIntegersToDayStrings(frontmatterLines)
+			if !modified {
+				return content, false, nil
+			}
+
+			// Reconstruct the content
+			newContent := reconstructContent(result, markdown)
+			expiresIntegerCodemodLog.Print("Applied expires integer-to-string migration")
+			return newContent, true, nil
+		},
+	}
+}
+
+// convertExpiresIntegersToDayStrings converts integer expires values to day strings within safe-outputs blocks.
+// Only affects expires lines nested inside a safe-outputs block.
+func convertExpiresIntegersToDayStrings(lines []string) ([]string, bool) {
+	var result []string
+	var modified bool
+	var inSafeOutputsBlock bool
+	var safeOutputsIndent string
+
+	for i, line := range lines {
+		trimmedLine := strings.TrimSpace(line)
+
+		// Track if we're in the safe-outputs block
+		if strings.HasPrefix(trimmedLine, "safe-outputs:") {
+			inSafeOutputsBlock = true
+			safeOutputsIndent = getIndentation(line)
+			result = append(result, line)
+			continue
+		}
+
+		// Check if we've left the safe-outputs block
+		if inSafeOutputsBlock && len(trimmedLine) > 0 && !strings.HasPrefix(trimmedLine, "#") {
+			if hasExitedBlock(line, safeOutputsIndent) {
+				inSafeOutputsBlock = false
+			}
+		}
+
+		// Convert integer expires to day string if inside safe-outputs block
+		if inSafeOutputsBlock && strings.HasPrefix(trimmedLine, "expires:") {
+			newLine, converted := convertExpiresLineToString(line)
+			if converted {
+				result = append(result, newLine)
+				modified = true
+				expiresIntegerCodemodLog.Printf("Converted integer expires to day string on line %d", i+1)
+				continue
+			}
+		}
+
+		result = append(result, line)
+	}
+
+	return result, modified
+}
+
+// convertExpiresLineToString converts an expires line with an integer value to use a day string.
+// For example: "    expires: 7" -> "    expires: 7d"
+// Lines that already use a string format (e.g., "expires: 7d", "expires: 24h") are left unchanged.
+// Returns the (possibly converted) line and whether a conversion was made.
+func convertExpiresLineToString(line string) (string, bool) {
+	indent := getIndentation(line)
+	trimmedLine := strings.TrimSpace(line)
+
+	// Extract the value part after "expires:"
+	valuePart := strings.TrimPrefix(trimmedLine, "expires:")
+
+	// Match an integer value optionally followed by whitespace and a comment
+	matches := expiresIntegerValuePattern.FindStringSubmatch(valuePart)
+	if matches == nil {
+		// Not an integer value (already a string like "7d" or "false")
+		return line, false
+	}
+
+	intValue := matches[2]   // the digits
+	trailingWS := matches[3] // whitespace between value and comment
+	comment := matches[4]    // optional trailing comment
+
+	// Build the new line, preserving any trailing comment
+	if comment != "" {
+		return fmt.Sprintf("%sexpires: %sd%s%s", indent, intValue, trailingWS, comment), true
+	}
+	return fmt.Sprintf("%sexpires: %sd", indent, intValue), true
+}