Re-vendor the shared files from sneak/prompts at 0653579 (closes #52)

Takes .golangci.yml, .dockerignore, .gitignore, .editorconfig, the
workflow and REPO_POLICIES.md from sneak/prompts 0653579, with this
repository's own entries after the shared content. Lint (golangci-lint
v2.14.0) and test are Dockerfile phases that script/lint and script/test
build alone with a new CACHEBUST value, keeping Go's and golangci-lint's
caches; the image build depends on both. make fmt and make fmt-check also
format the markdown with prettier, pinned in yarn.lock. The agent
guidance moves to AGENTS.md. The Go code is fixed for what the new
configuration finds, and the AS and prefix detail reads now return the
rows' error after their loops.

Model: opus-5-5

internal/whois/whois.go

@@ -98,7 +98,8 @@ func (c *Client) LookupASN(ctx context.Context, asn int) (*ASNInfo, error) {
 	if err != nil {
 		// Return partial data from IANA if RIR query fails
 		info := c.parseResponse(asn, rir, ianaResp)
-		info.RawResponse = ianaResp + "\n--- RIR query failed: " + err.Error() + " ---\n"
+		info.RawResponse = fmt.Sprintf("%s\n--- RIR query failed: %v ---\n",
+			ianaResp, err)
 
 		return info, nil
 	}
@@ -120,28 +121,33 @@ func (c *Client) query(ctx context.Context, server, query string) (string, error
 	defer func() { _ = conn.Close() }()
 
 	// Set deadlines
-	if err := conn.SetWriteDeadline(time.Now().Add(writeTimeout)); err != nil {
+	err = conn.SetWriteDeadline(time.Now().Add(writeTimeout))
+	if err != nil {
 		return "", fmt.Errorf("set write deadline: %w", err)
 	}
 
 	// Send query
-	if _, err := fmt.Fprintf(conn, "%s\r\n", query); err != nil {
+	_, err = fmt.Fprintf(conn, "%s\r\n", query)
+	if err != nil {
 		return "", fmt.Errorf("write query: %w", err)
 	}
 
 	// Read response
-	if err := conn.SetReadDeadline(time.Now().Add(readTimeout)); err != nil {
+	err = conn.SetReadDeadline(time.Now().Add(readTimeout))
+	if err != nil {
 		return "", fmt.Errorf("set read deadline: %w", err)
 	}
 
 	var sb strings.Builder
+
 	scanner := bufio.NewScanner(conn)
 	for scanner.Scan() {
 		sb.WriteString(scanner.Text())
 		sb.WriteString("\n")
 	}
 
-	if err := scanner.Err(); err != nil {
+	err = scanner.Err()
+	if err != nil {
 		return sb.String(), fmt.Errorf("read response: %w", err)
 	}
 
@@ -149,10 +155,10 @@ func (c *Client) query(ctx context.Context, server, query string) (string, error
 }
 
 // parseIANAReferral extracts the RIR and WHOIS server from an IANA response.
-func (c *Client) parseIANAReferral(response string) (rir, whoisServer string) {
-	lines := strings.Split(response, "\n")
+func (c *Client) parseIANAReferral(response string) (string, string) {
+	var rir string
 
-	for _, line := range lines {
+	for line := range strings.SplitSeq(response, "\n") {
 		line = strings.TrimSpace(line)
 
 		// Look for "refer:" line
@@ -183,18 +189,9 @@ func (c *Client) parseIANAReferral(response string) (rir, whoisServer string) {
 
 		// Also check organisation line for RIR hints
 		if strings.HasPrefix(strings.ToLower(line), "organisation:") {
-			org := strings.ToLower(line)
-			switch {
-			case strings.Contains(org, "arin"):
-				rir = RIRARIN
-			case strings.Contains(org, "ripe"):
-				rir = RIRRIPE
-			case strings.Contains(org, "apnic"):
-				rir = RIRAPNIC
-			case strings.Contains(org, "lacnic"):
-				rir = RIRLACNIC
-			case strings.Contains(org, "afrinic"):
-				rir = RIRAFRNIC
+			orgRIR := rirInOrganisationLine(strings.ToLower(line))
+			if orgRIR != "" {
+				rir = orgRIR
 			}
 		}
 	}
@@ -202,6 +199,25 @@ func (c *Client) parseIANAReferral(response string) (rir, whoisServer string) {
 	return rir, ""
 }
 
+// rirInOrganisationLine returns the RIR a lowercased IANA "organisation:"
+// line names, or "" when it names none.
+func rirInOrganisationLine(org string) string {
+	switch {
+	case strings.Contains(org, "arin"):
+		return RIRARIN
+	case strings.Contains(org, "ripe"):
+		return RIRRIPE
+	case strings.Contains(org, "apnic"):
+		return RIRAPNIC
+	case strings.Contains(org, "lacnic"):
+		return RIRLACNIC
+	case strings.Contains(org, "afrinic"):
+		return RIRAFRNIC
+	default:
+		return ""
+	}
+}
+
 // parseResponse extracts ASN information from a WHOIS response.
 func (c *Client) parseResponse(asn int, rir, response string) *ASNInfo {
 	info := &ASNInfo{
@@ -211,11 +227,13 @@ func (c *Client) parseResponse(asn int, rir, response string) *ASNInfo {
 	}
 
 	lines := strings.Split(response, "\n")
+
 	var addressLines []string
 
 	for _, line := range lines {
 		line = strings.TrimSpace(line)
-		if line == "" || strings.HasPrefix(line, "%") || strings.HasPrefix(line, "#") {
+		if line == "" || strings.HasPrefix(line, "%") ||
+			strings.HasPrefix(line, "#") {
 			continue
 		}
 
@@ -232,63 +250,14 @@ func (c *Client) parseResponse(asn int, rir, response string) *ASNInfo {
 			continue
 		}
 
-		switch key {
-		// AS Name (varies by RIR)
-		case "asname", "as-name":
-			if info.ASName == "" {
-				info.ASName = value
-			}
-
-		// Organization
-		case "orgname", "org-name", "owner":
-			if info.OrgName == "" {
-				info.OrgName = value
-			}
-		case "orgid", "org-id", "org":
-			if info.OrgID == "" {
-				info.OrgID = value
-			}
-
 		// Address (collect multiple lines)
-		case "address":
+		if key == "address" {
 			addressLines = append(addressLines, value)
 
-		// Country
-		case "country":
-			if info.CountryCode == "" && len(value) == 2 {
-				info.CountryCode = strings.ToUpper(value)
-			}
-
-		// Abuse contact
-		case "orgabuseemail", "abuse-mailbox":
-			if info.AbuseEmail == "" {
-				info.AbuseEmail = value
-			}
-		case "orgabusephone":
-			if info.AbusePhone == "" {
-				info.AbusePhone = value
-			}
-
-		// Tech contact
-		case "orgtechemail":
-			if info.TechEmail == "" {
-				info.TechEmail = value
-			}
-		case "orgtechphone":
-			if info.TechPhone == "" {
-				info.TechPhone = value
-			}
-
-		// Registration dates
-		case "regdate", "created":
-			if info.RegDate == nil {
-				info.RegDate = c.parseDate(value)
-			}
-		case "updated", "last-modified", "changed":
-			if info.LastMod == nil {
-				info.LastMod = c.parseDate(value)
-			}
+			continue
 		}
+
+		c.setResponseField(info, key, value)
 	}
 
 	// Combine address lines
@@ -304,6 +273,65 @@ func (c *Client) parseResponse(asn int, rir, response string) *ASNInfo {
 	return info
 }
 
+// setResponseField stores the value of one "key: value" line of a WHOIS
+// response in info, keeping the first value seen for each field.
+func (c *Client) setResponseField(info *ASNInfo, key, value string) {
+	switch key {
+	// Country
+	case "country":
+		if info.CountryCode == "" && len(value) == 2 {
+			info.CountryCode = strings.ToUpper(value)
+		}
+
+	// Registration dates
+	case "regdate", "created":
+		if info.RegDate == nil {
+			info.RegDate = c.parseDate(value)
+		}
+	case "updated", "last-modified", "changed":
+		if info.LastMod == nil {
+			info.LastMod = c.parseDate(value)
+		}
+
+	default:
+		field := textFieldForKey(info, key)
+		if field != nil && *field == "" {
+			*field = value
+		}
+	}
+}
+
+// textFieldForKey returns the text field of info that a WHOIS response key
+// fills, or nil when the key fills none.
+func textFieldForKey(info *ASNInfo, key string) *string {
+	switch key {
+	// AS Name (varies by RIR)
+	case "asname", "as-name":
+		return &info.ASName
+
+	// Organization
+	case "orgname", "org-name", "owner":
+		return &info.OrgName
+	case "orgid", "org-id", "org":
+		return &info.OrgID
+
+	// Abuse contact
+	case "orgabuseemail", "abuse-mailbox":
+		return &info.AbuseEmail
+	case "orgabusephone":
+		return &info.AbusePhone
+
+	// Tech contact
+	case "orgtechemail":
+		return &info.TechEmail
+	case "orgtechphone":
+		return &info.TechPhone
+
+	default:
+		return nil
+	}
+}
+
 // parseDate attempts to parse various date formats used in WHOIS responses.
 func (c *Client) parseDate(value string) *time.Time {
 	// Common formats
@@ -319,15 +347,15 @@ func (c *Client) parseDate(value string) *time.Time {
 	value = strings.TrimSpace(value)
 	// Handle "YYYYMMDD" format from LACNIC
 	if len(value) == lacnicDateFormatLen {
-		if _, err := time.Parse("20060102", value); err == nil {
-			t, _ := time.Parse("20060102", value)
-
+		t, err := time.Parse("20060102", value)
+		if err == nil {
 			return &t
 		}
 	}
 
 	for _, format := range formats {
-		if t, err := time.Parse(format, value); err == nil {
+		t, err := time.Parse(format, value)
+		if err == nil {
 			return &t
 		}
 	}