first commit

pigo/internal/cli/btw/btw_config_test.go

@@ -0,0 +1,146 @@
+package btw
+
+// Tests for the /btw model/thinking override config (#282, US-005): btw.json
+// overlays the session defaults for the side thread only, is read fresh each
+// call, and falls back silently on missing/empty/partial config.
+
+import (
+	"bytes"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/smallnest/pigo/internal/agentcore"
+	"github.com/smallnest/pigo/internal/cli"
+)
+
+// fakeHost satisfies cli.Host by embedding the interface (so every method is
+// present) while overriding only Live(), the sole accessor ResolveBtwSettings
+// reads. The embedded nil interface would panic if any other method were
+// called, which these tests never do.
+type fakeHost struct {
+	cli.Host
+	live *cli.LiveConfig
+}
+
+func (f fakeHost) Live() *cli.LiveConfig { return f.live }
+
+// withBtwConfig points PIGO_HOME at a temp dir and writes btw.json with the
+// given contents (or removes it when contents is ""), returning nothing — the
+// temp dir is cleaned up by t.TempDir. It restores PIGO_HOME after the test.
+func withBtwConfig(t *testing.T, contents string) {
+	t.Helper()
+	dir := t.TempDir()
+	t.Setenv("PIGO_HOME", dir)
+	if contents != "" {
+		if err := os.WriteFile(filepath.Join(dir, "btw.json"), []byte(contents), 0o644); err != nil {
+			t.Fatalf("write btw.json: %v", err)
+		}
+	}
+}
+
+// TestBtwConfigAbsentInherits verifies that with no btw.json the side settings
+// equal the session defaults.
+func TestBtwConfigAbsentInherits(t *testing.T) {
+	withBtwConfig(t, "") // no file
+	live := &cli.LiveConfig{Model: "sess-model", ProviderName: "sess-prov", ThinkingLevel: agentcore.ThinkingMedium}
+	host := fakeHost{live: live}
+
+	var warn bytes.Buffer
+	s := ResolveBtwSettings(&warn, host)
+	if s.Model != live.Model || s.ProviderName != live.ProviderName {
+		t.Errorf("absent config must inherit model/provider, got %q/%q", s.Model, s.ProviderName)
+	}
+	if s.ThinkingLevel != agentcore.ThinkingMedium {
+		t.Errorf("absent config must inherit thinkingLevel, got %q", s.ThinkingLevel)
+	}
+	if warn.Len() != 0 {
+		t.Errorf("absent config must not warn, got %q", warn.String())
+	}
+}
+
+// TestBtwConfigEmptyObjectInherits verifies that an empty JSON object inherits
+// everything without warning.
+func TestBtwConfigEmptyObjectInherits(t *testing.T) {
+	withBtwConfig(t, "{}")
+	live := &cli.LiveConfig{Model: "sess-model", ThinkingLevel: agentcore.ThinkingLow}
+	host := fakeHost{live: live}
+
+	var warn bytes.Buffer
+	s := ResolveBtwSettings(&warn, host)
+	if s.Model != live.Model || s.ThinkingLevel != agentcore.ThinkingLow {
+		t.Errorf("empty object must inherit, got model=%q thinking=%q", s.Model, s.ThinkingLevel)
+	}
+	if warn.Len() != 0 {
+		t.Errorf("empty object must not warn, got %q", warn.String())
+	}
+}
+
+// TestBtwConfigThinkingOverride verifies a valid thinkingLevel is applied while
+// the model still inherits (partial config falls back per-field).
+func TestBtwConfigThinkingOverride(t *testing.T) {
+	withBtwConfig(t, `{"thinkingLevel":"high"}`)
+	live := &cli.LiveConfig{Model: "sess-model", ThinkingLevel: agentcore.ThinkingLow}
+	host := fakeHost{live: live}
+
+	var warn bytes.Buffer
+	s := ResolveBtwSettings(&warn, host)
+	if s.ThinkingLevel != agentcore.ThinkingHigh {
+		t.Errorf("expected thinkingLevel override 'high', got %q", s.ThinkingLevel)
+	}
+	if s.Model != live.Model {
+		t.Errorf("model must still inherit when only thinkingLevel is set, got %q", s.Model)
+	}
+	if warn.Len() != 0 {
+		t.Errorf("valid override must not warn, got %q", warn.String())
+	}
+}
+
+// TestBtwConfigInvalidThinkingWarnsAndFallsBack verifies an invalid thinkingLevel
+// warns on one line and keeps the session value.
+func TestBtwConfigInvalidThinkingWarnsAndFallsBack(t *testing.T) {
+	withBtwConfig(t, `{"thinkingLevel":"bogus"}`)
+	live := &cli.LiveConfig{Model: "sess-model", ThinkingLevel: agentcore.ThinkingMedium}
+	host := fakeHost{live: live}
+
+	var warn bytes.Buffer
+	s := ResolveBtwSettings(&warn, host)
+	if s.ThinkingLevel != agentcore.ThinkingMedium {
+		t.Errorf("invalid thinkingLevel must fall back to session value, got %q", s.ThinkingLevel)
+	}
+	if !strings.Contains(warn.String(), "thinkingLevel") {
+		t.Errorf("expected a warning about the invalid thinkingLevel, got %q", warn.String())
+	}
+}
+
+// TestBtwConfigMalformedWarnsAndInherits verifies a malformed JSON file warns
+// once and inherits every field (never crashes /btw).
+func TestBtwConfigMalformedWarnsAndInherits(t *testing.T) {
+	withBtwConfig(t, `{not json`)
+	live := &cli.LiveConfig{Model: "sess-model", ThinkingLevel: agentcore.ThinkingLow}
+	host := fakeHost{live: live}
+
+	var warn bytes.Buffer
+	s := ResolveBtwSettings(&warn, host)
+	if s.Model != live.Model || s.ThinkingLevel != agentcore.ThinkingLow {
+		t.Errorf("malformed config must inherit, got model=%q thinking=%q", s.Model, s.ThinkingLevel)
+	}
+	if !strings.Contains(warn.String(), "invalid btw.json") {
+		t.Errorf("expected a malformed-config warning, got %q", warn.String())
+	}
+}
+
+// TestBtwConfigDoesNotMutateSession verifies ResolveBtwSettings never mutates
+// the session live config, so a /btw override cannot leak into the main session
+// (FR-8).
+func TestBtwConfigDoesNotMutateSession(t *testing.T) {
+	withBtwConfig(t, `{"thinkingLevel":"xhigh"}`)
+	live := &cli.LiveConfig{Model: "sess-model", ThinkingLevel: agentcore.ThinkingLow}
+	host := fakeHost{live: live}
+
+	_ = ResolveBtwSettings(&bytes.Buffer{}, host)
+	if live.ThinkingLevel != agentcore.ThinkingLow {
+		t.Errorf("session thinkingLevel must be unchanged by /btw config, got %q", live.ThinkingLevel)
+	}
+}