Add shared ConfigKit loading and runtime settings conversion

internal/config/load_test.go

@@ -0,0 +1,176 @@
+package config
+
+import (
+	"errors"
+	"os"
+	"path/filepath"
+	"reflect"
+	"strings"
+	"testing"
+
+	configkit "gitea.maximumdirect.net/eric/ConfigKit"
+)
+
+func useConfigSearchPaths(t *testing.T, paths ...string) {
+	t.Helper()
+	previous := defaultConfigSearchPaths
+	defaultConfigSearchPaths = paths
+	t.Cleanup(func() { defaultConfigSearchPaths = previous })
+}
+
+func writeApplicationFile(t *testing.T, path, body string) {
+	t.Helper()
+	if err := os.WriteFile(path, []byte(body), 0o600); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestLoadSelectsOrderedSourceAndKeepsItsSnapshot(t *testing.T) {
+	dir := t.TempDir()
+	first := filepath.Join(dir, "first.yml")
+	second := filepath.Join(dir, "second.yml")
+	writeApplicationFile(t, first, "prompt_dir: ./first\n")
+	writeApplicationFile(t, second, "prompt_dir: ./second\n")
+	useConfigSearchPaths(t, first, second)
+
+	result, err := Load(LoadOptions{Path: filepath.Join(dir, "ignored.yml")})
+	if err != nil {
+		t.Fatalf("load first implicit source: %v", err)
+	}
+	if result.Config.PromptDir != "first" || len(result.Sources()) != 1 || result.Sources()[0].Path != first {
+		t.Fatalf("unexpected implicit source: config=%+v sources=%+v", result.Config, result.Sources())
+	}
+	writeApplicationFile(t, first, "prompt_dir: ./changed\n")
+	if result.Config.PromptDir != "first" {
+		t.Fatalf("result did not retain resolved snapshot: %+v", result.Config)
+	}
+
+	if err := os.Remove(first); err != nil {
+		t.Fatal(err)
+	}
+	result, err = Load(LoadOptions{})
+	if err != nil || result.Config.PromptDir != "second" || result.Sources()[0].Path != second {
+		t.Fatalf("second implicit source not selected: result=%+v err=%v", result, err)
+	}
+
+	result, err = Load(LoadOptions{Path: first, Explicit: true})
+	if result != nil || err == nil {
+		t.Fatalf("missing explicit source was accepted: result=%+v err=%v", result, err)
+	}
+	var loadError *configkit.LoadError
+	if !errors.As(err, &loadError) {
+		t.Fatalf("typed load error was lost: %v", err)
+	}
+}
+
+func TestLoadRejectsExplicitEmptyAndDistinguishesEmptyFile(t *testing.T) {
+	useConfigSearchPaths(t, filepath.Join(t.TempDir(), "absent.yml"))
+	if _, err := Load(LoadOptions{Explicit: true, Path: ""}); err == nil {
+		t.Fatal("explicit empty path was accepted")
+	} else {
+		var loadError *configkit.LoadError
+		if !errors.As(err, &loadError) {
+			t.Fatalf("expected upstream source diagnostic, got %v", err)
+		}
+	}
+
+	dir := t.TempDir()
+	empty := filepath.Join(dir, "empty.yml")
+	writeApplicationFile(t, empty, "")
+	if _, err := Load(LoadOptions{Path: empty, Explicit: true}); err == nil {
+		t.Fatal("empty file was treated as defaults-only")
+	}
+	writeApplicationFile(t, empty, "{}\n")
+	result, err := Load(LoadOptions{Path: empty, Explicit: true})
+	if err != nil || !reflect.DeepEqual(result.Config, documentDefaults()) {
+		t.Fatalf("empty mapping did not load defaults: result=%+v err=%v", result, err)
+	}
+}
+
+func TestLoadDefaultsOnlyAndOverridesBeforeValidation(t *testing.T) {
+	useConfigSearchPaths(t, filepath.Join(t.TempDir(), "absent.yml"))
+	result, err := Load(LoadOptions{})
+	if err != nil || !reflect.DeepEqual(result.Config, documentDefaults()) || len(result.Sources()) != 0 {
+		t.Fatalf("defaults-only load: result=%+v err=%v", result, err)
+	}
+
+	result, err = Load(LoadOptions{Overrides: []configkit.Override{{
+		Path: configkit.Keys("server", "max_request_bytes"), Value: int64(0), Flag: "--max-request-bytes",
+	}}})
+	if err != nil || result.Config.Server.MaxRequestBytes != 0 || len(result.Sources()) != 1 || result.Sources()[0].Layer != configkit.LayerCLI {
+		t.Fatalf("defaults-only override lost: result=%+v err=%v", result, err)
+	}
+
+	path := filepath.Join(t.TempDir(), "invalid.yml")
+	writeApplicationFile(t, path, "defaults:\n  render_format: invalid-choice\n")
+	result, err = Load(LoadOptions{Path: path, Explicit: true, Overrides: []configkit.Override{{
+		Path: configkit.Keys("defaults", "render_format"), Value: "json", Flag: "--render-format",
+	}}})
+	if err != nil || result.Config.Defaults.RenderFormat != "json" {
+		t.Fatalf("override did not precede validation: result=%+v err=%v", result, err)
+	}
+	if len(result.Sources()) != 2 || result.Sources()[0].Layer != configkit.LayerBase || result.Sources()[1].Layer != configkit.LayerCLI {
+		t.Fatalf("source order changed: %+v", result.Sources())
+	}
+	writeApplicationFile(t, path, "defaults: [\n")
+	if _, err := Load(LoadOptions{Path: path, Explicit: true, Overrides: []configkit.Override{{
+		Path: configkit.Keys("defaults", "render_format"), Value: "json", Flag: "--render-format",
+	}}}); err == nil {
+		t.Fatal("override bypassed malformed lower-level YAML")
+	}
+}
+
+func TestSettingsCopiesResolvedValuesAndSortsBackends(t *testing.T) {
+	result, err := loadDocumentBytes(`schema_dir: ""
+transient_retries: 0
+server:
+  addr: ""
+  artifact_root: ""
+  max_request_bytes: 0
+defaults:
+  render_format: json
+backends:
+  zed:
+    endpoint: http://zed.invalid/v1
+    extra_params:
+      count: 4
+  alpha:
+    queue_capacity: 0
+`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	settings := Settings(result.Config)
+	if settings.SchemaDir != "" || settings.ServerAddr != "" || settings.MaxRequestBytes != 0 || settings.DefaultRenderFormat != "json" {
+		t.Fatalf("resolved scalar values changed: %+v", settings)
+	}
+	if settings.TransientRetries == nil || *settings.TransientRetries != 0 {
+		t.Fatalf("retry presence lost: %+v", settings.TransientRetries)
+	}
+	if len(settings.Backends) != 2 || settings.Backends[0].ID != "alpha" || settings.Backends[1].ID != "zed" {
+		t.Fatalf("backend order changed: %+v", settings.Backends)
+	}
+	if settings.Backends[0].QueueCapacity == nil || *settings.Backends[0].QueueCapacity != 0 || settings.Backends[1].QueueCapacity != nil {
+		t.Fatalf("queue presence changed: %+v", settings.Backends)
+	}
+	if value := settings.Backends[1].ExtraParams["count"]; value != int64(4) {
+		t.Fatalf("dynamic number changed shape: %T %v", value, value)
+	}
+
+	if got := Settings(documentDefaults()); got.TransientRetries != nil || got.Backends != nil {
+		t.Fatalf("default nullable values changed: %+v", got)
+	}
+}
+
+func TestLoadDiscoveryErrorQuotesPath(t *testing.T) {
+	dir := t.TempDir()
+	loop := filepath.Join(dir, "loop-\n.yml")
+	if err := os.Symlink(loop, loop); err != nil {
+		t.Skipf("symlink unavailable: %v", err)
+	}
+	useConfigSearchPaths(t, loop)
+	_, err := Load(LoadOptions{})
+	if err == nil || !strings.Contains(err.Error(), `\n`) || strings.Contains(err.Error(), "loop-\n.yml") {
+		t.Fatalf("discovery error did not quote path safely: %v", err)
+	}
+}