Files
beads/internal/utils/issue_id.go
Shaun Cutts d541ff48e3 fix: accept 3-char all-letter base36 hashes in ExtractIssuePrefix (#446)
isLikelyHash() required at least one digit to distinguish hashes from
English words, but base36 hashes can be all-letters by chance.

This caused ExtractIssuePrefix("xa-adt-bat") to return "xa" instead
of "xa-adt", breaking import for 20 issues in xa-adapt.

Fix: Accept all-letter suffixes for 3-char only, keep digit requirement
for 4+ chars where word collision probability is low enough (~0.2%).

Rationale:
- 3-char: 36³ = 46K hashes, ~1000 common words = ~2% collision
- 4-char: 36⁴ = 1.6M hashes, ~3000 words = ~0.2% collision
- 5+ char: collision rate negligible
2025-12-02 23:00:24 -08:00

94 lines
2.9 KiB
Go

package utils
import (
"fmt"
"strings"
)
// ExtractIssuePrefix extracts the prefix from an issue ID like "bd-123" -> "bd"
// Uses the last hyphen before a numeric or hash suffix:
// - "beads-vscode-1" -> "beads-vscode" (numeric suffix)
// - "web-app-a3f8e9" -> "web-app" (hash suffix)
// - "my-cool-app-123" -> "my-cool-app" (numeric suffix)
// Only uses first hyphen for non-ID suffixes like "vc-baseline-test" -> "vc"
func ExtractIssuePrefix(issueID string) string {
// Try last hyphen first (handles multi-part prefixes like "beads-vscode-1")
lastIdx := strings.LastIndex(issueID, "-")
if lastIdx <= 0 {
return ""
}
suffix := issueID[lastIdx+1:]
// Check if suffix looks like an issue ID component (numeric or hash-like)
if len(suffix) > 0 {
// Extract just the numeric part (handle "123.1.2" -> check "123")
numPart := suffix
if dotIdx := strings.Index(suffix, "."); dotIdx > 0 {
numPart = suffix[:dotIdx]
}
// Check if it's numeric
var num int
if _, err := fmt.Sscanf(numPart, "%d", &num); err == nil {
// Suffix is numeric, use last hyphen
return issueID[:lastIdx]
}
// Check if it looks like a hash (hexadecimal characters, 4+ chars)
// Hash IDs are typically 4-8 hex characters (e.g., "a3f8e9", "1a2b")
if isLikelyHash(numPart) {
// Suffix looks like a hash, use last hyphen
return issueID[:lastIdx]
}
}
// Suffix is not numeric or hash-like (e.g., "vc-baseline-test"), fall back to first hyphen
firstIdx := strings.Index(issueID, "-")
if firstIdx <= 0 {
return ""
}
return issueID[:firstIdx]
}
// isLikelyHash checks if a string looks like a hash ID suffix.
// Returns true for base36 strings of 3-8 characters (0-9, a-z).
//
// For 3-char suffixes: accepts all base36 (including all-letter like "bat", "dev").
// For 4+ char suffixes: requires at least one digit to distinguish from English words.
//
// Rationale (word collision probability):
// - 3-char: 36³ = 46K hashes, ~1000 common words = ~2% (accept false positives)
// - 4-char: 36⁴ = 1.6M hashes, ~3000 words = ~0.2% (digit requirement is safe)
// - 5+ char: collision rate negligible
//
// Hash IDs in beads use adaptive length scaling from 3-8 characters.
func isLikelyHash(s string) bool {
if len(s) < 3 || len(s) > 8 {
return false
}
// 3-char suffixes get a free pass (word collision acceptable)
// 4+ char suffixes require at least one digit
hasDigit := len(s) == 3
// Check if all characters are base36 (0-9, a-z)
for _, c := range s {
if c >= '0' && c <= '9' {
hasDigit = true
}
if !((c >= '0' && c <= '9') || (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {
return false
}
}
return hasDigit
}
// ExtractIssueNumber extracts the number from an issue ID like "bd-123" -> 123
func ExtractIssueNumber(issueID string) int {
idx := strings.LastIndex(issueID, "-")
if idx < 0 || idx == len(issueID)-1 {
return 0
}
var num int
_, _ = fmt.Sscanf(issueID[idx+1:], "%d", &num)
return num
}