fix: Compose generator should detect duplicate service names at generate-time (#850)

lib/generators.sh

@@ -66,6 +66,27 @@ _get_primary_woodpecker_repo_id() {
   echo "$max_id"
 }
 
+# Track service names to detect duplicates at generate-time.
+# Associative arrays for O(1) lookup of seen services and their sources.
+declare -A _seen_services
+declare -A _service_sources
+
+# Record a service name and source; return 1 if duplicate detected.
+_record_service() {
+  local service_name="$1"
+  local source="$2"
+  if [ -n "${_seen_services[$service_name]:-}" ]; then
+    local original_source="${_service_sources[$service_name]}"
+    echo "ERROR: Duplicate service name '$service_name' detected —" >&2
+    echo "  '$service_name' emitted twice — from $original_source and from $source" >&2
+    echo "  Remove one of the conflicting activations to proceed." >&2
+    return 1
+  fi
+  _seen_services[$service_name]=1
+  _service_sources[$service_name]="$source"
+  return 0
+}
+
 # Parse project TOML for local-model agents and emit compose services.
 # Writes service definitions to stdout; caller handles insertion into compose file.
 _generate_local_model_services() {
@@ -97,6 +118,16 @@ _generate_local_model_services() {
         POLL_INTERVAL) poll_interval_val="$value" ;;
         ---)
           if [ -n "$service_name" ] && [ -n "$base_url" ]; then
+            # Record service for duplicate detection using the full service name
+            local full_service_name="agents-${service_name}"
+            local toml_basename
+            toml_basename=$(basename "$toml")
+            if ! _record_service "$full_service_name" "[agents.$service_name] in projects/$toml_basename"; then
+              # Duplicate detected — clean up and abort
+              rm -f "$temp_file"
+              return 1
+            fi
+
             # Per-agent FORGE_TOKEN / FORGE_PASS lookup (#834 Gap 3).
             # Two hired llama agents must not share the same Forgejo identity,
             # so we key the env-var lookup by forge_user (which hire-agent.sh
@@ -282,6 +313,28 @@ _generate_compose_impl() {
     return 0
   fi
 
+  # Initialize duplicate detection with base services defined in the template
+  _record_service "agents" "base compose template" || return 1
+  _record_service "forgejo" "base compose template" || return 1
+  _record_service "woodpecker" "base compose template" || return 1
+  _record_service "woodpecker-agent" "base compose template" || return 1
+  _record_service "runner" "base compose template" || return 1
+  _record_service "edge" "base compose template" || return 1
+  _record_service "staging" "base compose template" || return 1
+  _record_service "staging-deploy" "base compose template" || return 1
+  _record_service "chat" "base compose template" || return 1
+
+  # Check for legacy ENABLE_LLAMA_AGENT (now rejected at runtime, but check here)
+  # This ensures clear error message at generate-time, not at container startup
+  if [ "${ENABLE_LLAMA_AGENT:-0}" = "1" ]; then
+    if ! _record_service "agents-llama" "ENABLE_LLAMA_AGENT=1"; then
+      return 1
+    fi
+    if ! _record_service "agents-llama-all" "ENABLE_LLAMA_AGENT=1"; then
+      return 1
+    fi
+  fi
+
   # Extract primary woodpecker_repo_id from project TOML files
   local wp_repo_id
   wp_repo_id=$(_get_primary_woodpecker_repo_id)
@@ -633,7 +686,10 @@ COMPOSEEOF
   fi
 
   # Append local-model agent services if any are configured
-  _generate_local_model_services "$compose_file"
+  if ! _generate_local_model_services "$compose_file"; then
+    echo "ERROR: Failed to generate local-model agent services. See errors above." >&2
+    return 1
+  fi
 
   # Resolve the Claude CLI binary path and persist as CLAUDE_BIN_DIR in .env.
   # docker-compose.yml references ${CLAUDE_BIN_DIR} so the value must be set.