From 314f8c31f202d3f92b5a050cce629dd89363f76e Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Tue, 7 Jul 2026 06:45:33 +0000
Subject: [PATCH 1/8] Initial plan


From 5b2624c84ee3797cf77312267a656ce355c533d9 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 16 Jul 2026 03:56:17 +0000
Subject: [PATCH 2/8] feat(config): implement expect field in CaseDefaults with
 merge logic

---
 internal/config/schema.go            |   5 +
 internal/evaluator/evaluator.go      | 100 ++++++-
 internal/evaluator/evaluator_test.go | 372 +++++++++++++++++++++++++++
 3 files changed, 476 insertions(+), 1 deletion(-)

diff --git a/internal/config/schema.go b/internal/config/schema.go
index f59169ec..9b62713e 100644
--- a/internal/config/schema.go
+++ b/internal/config/schema.go
@@ -176,6 +176,11 @@ type CaseDefaults struct {
 	// path, regardless of whether the agent succeeded, failed, or timed out.
 	// Per-case CaseConfig.CollectArtifacts is merged (union) on top of this.
 	CollectArtifacts []string `yaml:"collect_artifacts,omitempty"`
+	// Expect provides default expect checks applied to all cases. Per-case
+	// Expect is merged on top: slice fields (must_contain, must_not_contain,
+	// files_exist, files_not_exist, file_contains) are appended; scalar fields
+	// (exit_code, golden_file) are overridden when set at the case level.
+	Expect Expect `yaml:"expect,omitempty"`
 }
 
 // RetryPolicy describes retry behavior.
diff --git a/internal/evaluator/evaluator.go b/internal/evaluator/evaluator.go
index bd790537..1a4a1b1c 100644
--- a/internal/evaluator/evaluator.go
+++ b/internal/evaluator/evaluator.go
@@ -509,7 +509,11 @@ func (e *defaultEvaluator) runExpectPreCheck(
 	turnsTotal int,
 	result *EvalResult,
 ) bool {
-	expectCfg := resolveExpectConfig(&caseCfg.Expect)
+	// Merge default expect with case-level expect
+	defaultExpect := &e.evalCfg.Cases.Defaults.Expect
+	mergedExpect := mergeExpectConfig(defaultExpect, &caseCfg.Expect)
+
+	expectCfg := resolveExpectConfig(&mergedExpect)
 	if expectCfg == nil {
 		return false
 	}
@@ -809,6 +813,100 @@ func resolveExpectConfig(expectCfg *config.Expect) *config.Expect {
 	return expectCfg
 }
 
+// mergeExpectConfig merges default expect checks with case-level expect.
+// Slice fields (must_contain, must_not_contain, files_exist, files_not_exist,
+// file_contains) are appended and de-duplicated. Scalar fields (exit_code,
+// golden_file) are overridden by the case when set.
+func mergeExpectConfig(defaults, caseExpect *config.Expect) config.Expect {
+	if defaults == nil {
+		return *caseExpect
+	}
+
+	merged := config.Expect{}
+
+	// Merge slice fields with de-duplication
+	merged.MustContain = mergeAndDeduplicate(defaults.MustContain, caseExpect.MustContain)
+	merged.MustNotContain = mergeAndDeduplicate(defaults.MustNotContain, caseExpect.MustNotContain)
+	merged.FilesExist = mergeAndDeduplicate(defaults.FilesExist, caseExpect.FilesExist)
+	merged.FilesNotExist = mergeAndDeduplicate(defaults.FilesNotExist, caseExpect.FilesNotExist)
+	merged.FileContains = mergeFileContains(defaults.FileContains, caseExpect.FileContains)
+
+	// Scalar fields: case overrides default when set
+	if caseExpect.ExitCode != nil {
+		merged.ExitCode = caseExpect.ExitCode
+	} else {
+		merged.ExitCode = defaults.ExitCode
+	}
+
+	if caseExpect.GoldenFile != "" {
+		merged.GoldenFile = caseExpect.GoldenFile
+	} else {
+		merged.GoldenFile = defaults.GoldenFile
+	}
+
+	return merged
+}
+
+// mergeAndDeduplicate merges two string slices and removes duplicates.
+func mergeAndDeduplicate(a, b []string) []string {
+	if len(a) == 0 && len(b) == 0 {
+		return nil
+	}
+
+	seen := make(map[string]bool)
+	var result []string
+
+	for _, s := range a {
+		if !seen[s] {
+			seen[s] = true
+			result = append(result, s)
+		}
+	}
+
+	for _, s := range b {
+		if !seen[s] {
+			seen[s] = true
+			result = append(result, s)
+		}
+	}
+
+	return result
+}
+
+// mergeFileContains merges two FileContainsCheck slices.
+// Duplicates (same path+content) are removed.
+func mergeFileContains(a, b []config.FileContainsCheck) []config.FileContainsCheck {
+	if len(a) == 0 && len(b) == 0 {
+		return nil
+	}
+
+	type key struct {
+		path    string
+		content string
+	}
+
+	seen := make(map[key]bool)
+	var result []config.FileContainsCheck
+
+	for _, check := range a {
+		k := key{path: check.Path, content: check.Content}
+		if !seen[k] {
+			seen[k] = true
+			result = append(result, check)
+		}
+	}
+
+	for _, check := range b {
+		k := key{path: check.Path, content: check.Content}
+		if !seen[k] {
+			seen[k] = true
+			result = append(result, check)
+		}
+	}
+
+	return result
+}
+
 func (e *defaultEvaluator) prepareRuntimeForCase(ctx context.Context, caseCfg *config.CaseConfig, configName string, ag agent.Agent) (runtime.Runtime, error) {
 	rtCfg := e.evalCfg.Environment.ToRuntimeConfig()
 	rtCfg.Delete = e.deleteWorkspace
diff --git a/internal/evaluator/evaluator_test.go b/internal/evaluator/evaluator_test.go
index 6dfe377c..9e25b7ba 100644
--- a/internal/evaluator/evaluator_test.go
+++ b/internal/evaluator/evaluator_test.go
@@ -2100,6 +2100,378 @@ func TestResolveExpectConfig(t *testing.T) {
 	}
 }
 
+func TestMergeExpectConfig(t *testing.T) {
+	t.Parallel()
+
+	exitCode0 := 0
+	exitCode1 := 1
+
+	tests := []struct {
+		name     string
+		defaults *config.Expect
+		caseExp  *config.Expect
+		expected config.Expect
+	}{
+		{
+			name:     "nil defaults returns case expect",
+			defaults: nil,
+			caseExp: &config.Expect{
+				MustContain: []string{"foo"},
+				ExitCode:    &exitCode0,
+			},
+			expected: config.Expect{
+				MustContain: []string{"foo"},
+				ExitCode:    &exitCode0,
+			},
+		},
+		{
+			name: "empty case returns defaults",
+			defaults: &config.Expect{
+				MustContain: []string{"default"},
+				ExitCode:    &exitCode0,
+			},
+			caseExp: &config.Expect{},
+			expected: config.Expect{
+				MustContain: []string{"default"},
+				ExitCode:    &exitCode0,
+			},
+		},
+		{
+			name: "slice fields are appended",
+			defaults: &config.Expect{
+				MustContain:    []string{"default1"},
+				MustNotContain: []string{"bad1"},
+				FilesExist:     []string{"file1.txt"},
+			},
+			caseExp: &config.Expect{
+				MustContain:    []string{"case1"},
+				MustNotContain: []string{"bad2"},
+				FilesExist:     []string{"file2.txt"},
+			},
+			expected: config.Expect{
+				MustContain:    []string{"default1", "case1"},
+				MustNotContain: []string{"bad1", "bad2"},
+				FilesExist:     []string{"file1.txt", "file2.txt"},
+			},
+		},
+		{
+			name: "duplicate strings are removed",
+			defaults: &config.Expect{
+				MustContain: []string{"foo", "bar"},
+				FilesExist:  []string{"a.txt", "b.txt"},
+			},
+			caseExp: &config.Expect{
+				MustContain: []string{"foo", "baz"},
+				FilesExist:  []string{"b.txt", "c.txt"},
+			},
+			expected: config.Expect{
+				MustContain: []string{"foo", "bar", "baz"},
+				FilesExist:  []string{"a.txt", "b.txt", "c.txt"},
+			},
+		},
+		{
+			name: "scalar fields: case overrides default exit_code",
+			defaults: &config.Expect{
+				ExitCode: &exitCode0,
+			},
+			caseExp: &config.Expect{
+				ExitCode: &exitCode1,
+			},
+			expected: config.Expect{
+				ExitCode: &exitCode1,
+			},
+		},
+		{
+			name: "scalar fields: default exit_code when case not set",
+			defaults: &config.Expect{
+				ExitCode: &exitCode0,
+			},
+			caseExp: &config.Expect{},
+			expected: config.Expect{
+				ExitCode: &exitCode0,
+			},
+		},
+		{
+			name: "scalar fields: case golden_file overrides default",
+			defaults: &config.Expect{
+				GoldenFile: "default.txt",
+			},
+			caseExp: &config.Expect{
+				GoldenFile: "case.txt",
+			},
+			expected: config.Expect{
+				GoldenFile: "case.txt",
+			},
+		},
+		{
+			name: "scalar fields: default golden_file when case not set",
+			defaults: &config.Expect{
+				GoldenFile: "default.txt",
+			},
+			caseExp: &config.Expect{},
+			expected: config.Expect{
+				GoldenFile: "default.txt",
+			},
+		},
+		{
+			name: "file_contains merges and deduplicates",
+			defaults: &config.Expect{
+				FileContains: []config.FileContainsCheck{
+					{Path: "a.txt", Content: "foo"},
+					{Path: "b.txt", Content: "bar"},
+				},
+			},
+			caseExp: &config.Expect{
+				FileContains: []config.FileContainsCheck{
+					{Path: "a.txt", Content: "foo"}, // duplicate
+					{Path: "c.txt", Content: "baz"},
+				},
+			},
+			expected: config.Expect{
+				FileContains: []config.FileContainsCheck{
+					{Path: "a.txt", Content: "foo"},
+					{Path: "b.txt", Content: "bar"},
+					{Path: "c.txt", Content: "baz"},
+				},
+			},
+		},
+		{
+			name: "complex merge: all fields",
+			defaults: &config.Expect{
+				MustContain:    []string{"default"},
+				MustNotContain: []string{"bad"},
+				ExitCode:       &exitCode0,
+				FilesExist:     []string{"default.txt"},
+				FilesNotExist:  []string{"bad.txt"},
+				GoldenFile:     "default_golden.txt",
+				FileContains:   []config.FileContainsCheck{{Path: "x.txt", Content: "y"}},
+			},
+			caseExp: &config.Expect{
+				MustContain:   []string{"case"},
+				ExitCode:      &exitCode1,
+				FilesExist:    []string{"case.txt"},
+				FilesNotExist: []string{"unwanted.txt"},
+				FileContains:  []config.FileContainsCheck{{Path: "z.txt", Content: "w"}},
+			},
+			expected: config.Expect{
+				MustContain:    []string{"default", "case"},
+				MustNotContain: []string{"bad"},
+				ExitCode:       &exitCode1, // case overrides
+				FilesExist:     []string{"default.txt", "case.txt"},
+				FilesNotExist:  []string{"bad.txt", "unwanted.txt"},
+				GoldenFile:     "default_golden.txt", // case didn't set, default remains
+				FileContains: []config.FileContainsCheck{
+					{Path: "x.txt", Content: "y"},
+					{Path: "z.txt", Content: "w"},
+				},
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := mergeExpectConfig(tt.defaults, tt.caseExp)
+
+			// Compare slices
+			if !stringSlicesEqual(result.MustContain, tt.expected.MustContain) {
+				t.Errorf("MustContain: got %v, want %v", result.MustContain, tt.expected.MustContain)
+			}
+			if !stringSlicesEqual(result.MustNotContain, tt.expected.MustNotContain) {
+				t.Errorf("MustNotContain: got %v, want %v", result.MustNotContain, tt.expected.MustNotContain)
+			}
+			if !stringSlicesEqual(result.FilesExist, tt.expected.FilesExist) {
+				t.Errorf("FilesExist: got %v, want %v", result.FilesExist, tt.expected.FilesExist)
+			}
+			if !stringSlicesEqual(result.FilesNotExist, tt.expected.FilesNotExist) {
+				t.Errorf("FilesNotExist: got %v, want %v", result.FilesNotExist, tt.expected.FilesNotExist)
+			}
+
+			// Compare scalars
+			if (result.ExitCode == nil) != (tt.expected.ExitCode == nil) {
+				t.Errorf("ExitCode nil mismatch: got %v, want %v", result.ExitCode, tt.expected.ExitCode)
+			} else if result.ExitCode != nil && *result.ExitCode != *tt.expected.ExitCode {
+				t.Errorf("ExitCode: got %d, want %d", *result.ExitCode, *tt.expected.ExitCode)
+			}
+
+			if result.GoldenFile != tt.expected.GoldenFile {
+				t.Errorf("GoldenFile: got %s, want %s", result.GoldenFile, tt.expected.GoldenFile)
+			}
+
+			// Compare FileContains
+			if !fileContainsSlicesEqual(result.FileContains, tt.expected.FileContains) {
+				t.Errorf("FileContains: got %v, want %v", result.FileContains, tt.expected.FileContains)
+			}
+		})
+	}
+}
+
+func TestMergeAndDeduplicate(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name     string
+		a        []string
+		b        []string
+		expected []string
+	}{
+		{
+			name:     "both nil",
+			a:        nil,
+			b:        nil,
+			expected: nil,
+		},
+		{
+			name:     "both empty",
+			a:        []string{},
+			b:        []string{},
+			expected: nil,
+		},
+		{
+			name:     "a nil, b has items",
+			a:        nil,
+			b:        []string{"x", "y"},
+			expected: []string{"x", "y"},
+		},
+		{
+			name:     "a has items, b nil",
+			a:        []string{"a", "b"},
+			b:        nil,
+			expected: []string{"a", "b"},
+		},
+		{
+			name:     "no duplicates",
+			a:        []string{"a", "b"},
+			b:        []string{"c", "d"},
+			expected: []string{"a", "b", "c", "d"},
+		},
+		{
+			name:     "with duplicates",
+			a:        []string{"a", "b", "c"},
+			b:        []string{"b", "c", "d"},
+			expected: []string{"a", "b", "c", "d"},
+		},
+		{
+			name:     "all duplicates",
+			a:        []string{"x", "y"},
+			b:        []string{"x", "y"},
+			expected: []string{"x", "y"},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := mergeAndDeduplicate(tt.a, tt.b)
+			if !stringSlicesEqual(result, tt.expected) {
+				t.Errorf("got %v, want %v", result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestMergeFileContains(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name     string
+		a        []config.FileContainsCheck
+		b        []config.FileContainsCheck
+		expected []config.FileContainsCheck
+	}{
+		{
+			name:     "both nil",
+			a:        nil,
+			b:        nil,
+			expected: nil,
+		},
+		{
+			name:     "both empty",
+			a:        []config.FileContainsCheck{},
+			b:        []config.FileContainsCheck{},
+			expected: nil,
+		},
+		{
+			name: "no duplicates",
+			a: []config.FileContainsCheck{
+				{Path: "a.txt", Content: "foo"},
+			},
+			b: []config.FileContainsCheck{
+				{Path: "b.txt", Content: "bar"},
+			},
+			expected: []config.FileContainsCheck{
+				{Path: "a.txt", Content: "foo"},
+				{Path: "b.txt", Content: "bar"},
+			},
+		},
+		{
+			name: "exact duplicates",
+			a: []config.FileContainsCheck{
+				{Path: "a.txt", Content: "foo"},
+				{Path: "b.txt", Content: "bar"},
+			},
+			b: []config.FileContainsCheck{
+				{Path: "a.txt", Content: "foo"},
+			},
+			expected: []config.FileContainsCheck{
+				{Path: "a.txt", Content: "foo"},
+				{Path: "b.txt", Content: "bar"},
+			},
+		},
+		{
+			name: "same path different content",
+			a: []config.FileContainsCheck{
+				{Path: "a.txt", Content: "foo"},
+			},
+			b: []config.FileContainsCheck{
+				{Path: "a.txt", Content: "bar"},
+			},
+			expected: []config.FileContainsCheck{
+				{Path: "a.txt", Content: "foo"},
+				{Path: "a.txt", Content: "bar"},
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := mergeFileContains(tt.a, tt.b)
+			if !fileContainsSlicesEqual(result, tt.expected) {
+				t.Errorf("got %v, want %v", result, tt.expected)
+			}
+		})
+	}
+}
+
+// Helper functions for test comparisons
+func stringSlicesEqual(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	if len(a) == 0 && len(b) == 0 {
+		return true
+	}
+	for i := range a {
+		if a[i] != b[i] {
+			return false
+		}
+	}
+	return true
+}
+
+func fileContainsSlicesEqual(a, b []config.FileContainsCheck) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	if len(a) == 0 && len(b) == 0 {
+		return true
+	}
+	for i := range a {
+		if a[i].Path != b[i].Path || a[i].Content != b[i].Content {
+			return false
+		}
+	}
+	return true
+}
+
 func TestEvalResult_Fields(t *testing.T) {
 	r := EvalResult{
 		CaseID:        "test-case",

From d490116348d452d56e6d5b523c03edbad32f237a Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 16 Jul 2026 03:57:55 +0000
Subject: [PATCH 3/8] test(evaluator): add integration tests for default expect
 behavior

---
 internal/evaluator/evaluator_test.go | 119 +++++++++++++++++++++++++++
 1 file changed, 119 insertions(+)

diff --git a/internal/evaluator/evaluator_test.go b/internal/evaluator/evaluator_test.go
index 9e25b7ba..5d546c28 100644
--- a/internal/evaluator/evaluator_test.go
+++ b/internal/evaluator/evaluator_test.go
@@ -1175,6 +1175,125 @@ func TestExecuteCase_ExpectPass_ThenJudge(t *testing.T) {
 	}
 }
 
+func TestExecuteCase_DefaultExpect_AppliedToCase(t *testing.T) {
+	// Test that default expect checks from CaseDefaults are applied
+	e := newTestEvaluator(EvalOptions{
+		Agent: &mockAgent{name: "test", output: "no default keyword"},
+		EvalCfg: &config.EvalConfig{
+			Cases: config.CasesConfig{
+				Defaults: config.CaseDefaults{
+					Expect: config.Expect{
+						MustContain: []string{"default-keyword"},
+					},
+				},
+			},
+		},
+	})
+
+	caseCfg := &config.CaseConfig{
+		ID:    "case-default-expect",
+		Title: "Default Expect Test",
+		Input: config.Input{Prompt: "test"},
+	}
+
+	result := e.executeCase(context.Background(), caseCfg, "with_skill", &mockRuntime{workspace: "/tmp/test"}, nil)
+
+	if result.Status != judge.StatusFail {
+		t.Errorf("expected FAIL status, got %s", result.Status)
+	}
+	if result.ExpectResult == nil {
+		t.Fatal("expected non-nil ExpectResult")
+	}
+	if result.ExpectResult.Passed {
+		t.Error("expected expect check to fail due to default expect")
+	}
+}
+
+func TestExecuteCase_DefaultExpect_MergedWithCaseExpect(t *testing.T) {
+	// Test that default and case-level expects are merged
+	e := newTestEvaluator(EvalOptions{
+		Agent: &mockAgent{name: "test", output: "has default-keyword and case-keyword"},
+		EvalCfg: &config.EvalConfig{
+			Cases: config.CasesConfig{
+				Defaults: config.CaseDefaults{
+					Expect: config.Expect{
+						MustContain: []string{"default-keyword"},
+					},
+				},
+			},
+		},
+	})
+
+	caseCfg := &config.CaseConfig{
+		ID:    "case-merged-expect",
+		Title: "Merged Expect Test",
+		Input: config.Input{Prompt: "test"},
+		Expect: config.Expect{
+			MustContain: []string{"case-keyword"},
+		},
+	}
+
+	result := e.executeCase(context.Background(), caseCfg, "with_skill", &mockRuntime{workspace: "/tmp/test"}, nil)
+
+	if result.Status != judge.StatusPass {
+		t.Errorf("expected PASS status, got %s", result.Status)
+	}
+	if result.ExpectResult == nil {
+		t.Fatal("expected non-nil ExpectResult")
+	}
+	if !result.ExpectResult.Passed {
+		t.Error("expected both default and case expect checks to pass")
+	}
+}
+
+func TestExecuteCase_DefaultExpect_CaseOverridesExitCode(t *testing.T) {
+	// Test that case-level exit_code overrides default
+	exitCode0 := 0
+	exitCode1 := 1
+	
+	e := newTestEvaluator(EvalOptions{
+		Agent: &mockAgent{
+			name: "test",
+			runFunc: func(ctx context.Context, rt runtime.Runtime, opts agent.ExecOptions, messages []transcript.Message) (*agent.SessionResult, error) {
+				return &agent.SessionResult{
+					FinalMessage: "result",
+					ExitCode:     1,
+				}, nil
+			},
+		},
+		EvalCfg: &config.EvalConfig{
+			Cases: config.CasesConfig{
+				Defaults: config.CaseDefaults{
+					Expect: config.Expect{
+						ExitCode: &exitCode0,
+					},
+				},
+			},
+		},
+	})
+
+	caseCfg := &config.CaseConfig{
+		ID:    "case-override-exitcode",
+		Title: "Override Exit Code Test",
+		Input: config.Input{Prompt: "test"},
+		Expect: config.Expect{
+			ExitCode: &exitCode1, // Case expects exit 1, should pass
+		},
+	}
+
+	result := e.executeCase(context.Background(), caseCfg, "with_skill", &mockRuntime{workspace: "/tmp/test"}, nil)
+
+	if result.Status != judge.StatusPass {
+		t.Errorf("expected PASS status (case exit_code overrides default), got %s", result.Status)
+	}
+	if result.ExpectResult == nil {
+		t.Fatal("expected non-nil ExpectResult")
+	}
+	if !result.ExpectResult.Passed {
+		t.Error("expected expect check to pass with case-level exit_code override")
+	}
+}
+
 func TestExecuteCase_RetryPolicyRetriesErrors(t *testing.T) {
 	t.Parallel()
 

From d5c5ca1832232c64f5e36d486c9515bdf49ebfc4 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 16 Jul 2026 03:59:29 +0000
Subject: [PATCH 4/8] docs: document default expect checks in eval.yaml

---
 docs/guide/writing-evals.md    | 43 ++++++++++++++++++++++++++++++++++
 docs/zh/guide/writing-evals.md | 43 ++++++++++++++++++++++++++++++++++
 2 files changed, 86 insertions(+)

diff --git a/docs/guide/writing-evals.md b/docs/guide/writing-evals.md
index 232c358a..af0b08be 100644
--- a/docs/guide/writing-evals.md
+++ b/docs/guide/writing-evals.md
@@ -98,6 +98,11 @@ cases:
     collect_artifacts:            # Glob patterns selecting workspace files to download (see below)
       - "**/*.json"
       - "report/**"
+    expect:                       # Default expect checks applied to all cases (see Expect section)
+      exit_code: 0
+      must_not_contain:
+        - "TODO"
+        - "I cannot"
   parallelism: 2                  # Case parallelism, default 1
   retry_policy:
     max_retries: 1
@@ -487,8 +492,46 @@ expect:
     - "output.json"
   files_not_exist:              # Files that must not exist
     - "temp.log"
+  file_contains:                # Files must contain specific text
+    - path: "review.md"
+      content: "security"
+  golden_file: "expected.txt"   # Compare output to golden file
 ```
 
+#### Default expect checks
+
+Define common expect checks once in `cases.defaults.expect` instead of repeating them in every case:
+
+```yaml
+# In eval.yaml
+cases:
+  defaults:
+    expect:
+      exit_code: 0
+      must_not_contain:
+        - "TODO"
+        - "I cannot"
+      files_exist:
+        - "result.json"
+```
+
+Each case can add to or override these defaults:
+
+```yaml
+# In case.yaml
+expect:
+  must_contain:
+    - "SPECIAL_OK"              # Added to defaults
+  exit_code: 1                  # Overrides default exit_code
+```
+
+**Merge semantics:**
+
+- **Slice fields** (`must_contain`, `must_not_contain`, `files_exist`, `files_not_exist`, `file_contains`) are **appended** and de-duplicated (defaults first).
+- **Scalar fields** (`exit_code`, `golden_file`) are **overridden** by the case when set.
+- If no case-level `expect` is defined, defaults are used as-is.
+- The merged expect runs before judge; a failing merged expect skips judge execution.
+
 ### judge: rule_based — deterministic rules
 
 Decide pass/fail by declarative rules — fully deterministic and reproducible:
diff --git a/docs/zh/guide/writing-evals.md b/docs/zh/guide/writing-evals.md
index 25663ea6..63b4b94b 100644
--- a/docs/zh/guide/writing-evals.md
+++ b/docs/zh/guide/writing-evals.md
@@ -97,6 +97,11 @@ cases:
     collect_artifacts:            # 用 glob 指定要下载的 workspace 产物文件（见下文）
       - "**/*.json"
       - "report/**"
+    expect:                       # 默认 expect 检查，应用于所有用例（见 Expect 章节）
+      exit_code: 0
+      must_not_contain:
+        - "TODO"
+        - "I cannot"
   parallelism: 2                  # 用例并行数，默认 1
   retry_policy:                   # 重试策略
     max_retries: 1
@@ -469,8 +474,46 @@ expect:
     - "output.json"
   files_not_exist:              # 期望这些文件不存在
     - "temp.log"
+  file_contains:                # 文件必须包含特定文本
+    - path: "review.md"
+      content: "security"
+  golden_file: "expected.txt"   # 与黄金文件比对输出
 ```
 
+#### 默认 expect 检查
+
+在 `cases.defaults.expect` 中一次性定义通用的 expect 检查，而不是在每个用例中重复：
+
+```yaml
+# 在 eval.yaml 中
+cases:
+  defaults:
+    expect:
+      exit_code: 0
+      must_not_contain:
+        - "TODO"
+        - "I cannot"
+      files_exist:
+        - "result.json"
+```
+
+每个用例可以添加或覆盖这些默认值：
+
+```yaml
+# 在 case.yaml 中
+expect:
+  must_contain:
+    - "SPECIAL_OK"              # 添加到默认检查
+  exit_code: 1                  # 覆盖默认的 exit_code
+```
+
+**合并语义：**
+
+- **切片字段**（`must_contain`、`must_not_contain`、`files_exist`、`files_not_exist`、`file_contains`）会被**追加**并去重（默认值在前）。
+- **标量字段**（`exit_code`、`golden_file`）在用例层面设置时会**覆盖**默认值。
+- 如果用例未定义 `expect`，则直接使用默认值。
+- 合并后的 expect 在 judge 之前运行；如果合并后的 expect 失败，会跳过 judge 执行。
+
 ### judge: rule_based — 确定性规则评估
 
 基于声明式规则判定用例是否通过，结果完全确定、可重复：

From b3eeca2ce90227220e6c3c03114c0af163abcd88 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 16 Jul 2026 04:00:29 +0000
Subject: [PATCH 5/8] docs(skill-upper): update references with default expect
 support

---
 skills/skill-upper/references/case-yaml.md | 10 ++++++++++
 skills/skill-upper/references/eval-yaml.md |  5 +++++
 2 files changed, 15 insertions(+)

diff --git a/skills/skill-upper/references/case-yaml.md b/skills/skill-upper/references/case-yaml.md
index cc6164e0..1eeeffff 100644
--- a/skills/skill-upper/references/case-yaml.md
+++ b/skills/skill-upper/references/case-yaml.md
@@ -88,10 +88,20 @@ expect:
     - "output.json"
   files_not_exist:
     - "temp.log"
+  file_contains:
+    - path: "review.md"
+      content: "security"
+  golden_file: "expected.txt"
 ```
 
 expect 不通过时，judge 会被跳过。用它来快速过滤明显不合格的输出，节省 token。
 
+**与 `cases.defaults.expect` 合并：**
+
+- 如果 `eval.yaml` 的 `cases.defaults.expect` 定义了默认检查（如 `exit_code: 0`, `must_not_contain: ["TODO"]`），每个用例的 expect 会与之合并
+- 切片字段（`must_contain`, `must_not_contain`, `files_exist`, `files_not_exist`, `file_contains`）追加去重；标量字段（`exit_code`, `golden_file`）由用例覆盖
+- 用例未设 expect 时，直接使用默认值
+
 ## 常见写法
 
 - **纯文本路由 Skill**：`expect.must_contain` + `judge.rule_based.output_contains`
diff --git a/skills/skill-upper/references/eval-yaml.md b/skills/skill-upper/references/eval-yaml.md
index efc3034b..2187bd96 100644
--- a/skills/skill-upper/references/eval-yaml.md
+++ b/skills/skill-upper/references/eval-yaml.md
@@ -37,6 +37,11 @@ cases:
     collect_artifacts:          # 可选：用 glob 采集 workspace 产物文件
       - "**/*.json"
       - "report/**"
+    expect:                     # 可选：默认 expect 检查，应用于所有用例
+      exit_code: 0
+      must_not_contain:
+        - "TODO"
+        - "I cannot"
   parallelism: 2
   retry_policy:
     max_retries: 1

From 7cc5a3e7ba0f5652da733509556babe20b6150b4 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 16 Jul 2026 04:04:52 +0000
Subject: [PATCH 6/8] fix: address linting issues in test code

---
 internal/evaluator/evaluator_test.go | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/internal/evaluator/evaluator_test.go b/internal/evaluator/evaluator_test.go
index 5d546c28..543437ad 100644
--- a/internal/evaluator/evaluator_test.go
+++ b/internal/evaluator/evaluator_test.go
@@ -1250,7 +1250,7 @@ func TestExecuteCase_DefaultExpect_CaseOverridesExitCode(t *testing.T) {
 	// Test that case-level exit_code overrides default
 	exitCode0 := 0
 	exitCode1 := 1
-	
+
 	e := newTestEvaluator(EvalOptions{
 		Agent: &mockAgent{
 			name: "test",
@@ -2219,6 +2219,7 @@ func TestResolveExpectConfig(t *testing.T) {
 	}
 }
 
+//nolint:funlen // Comprehensive table-driven test with multiple test cases
 func TestMergeExpectConfig(t *testing.T) {
 	t.Parallel()
 
@@ -2389,6 +2390,7 @@ func TestMergeExpectConfig(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
 			result := mergeExpectConfig(tt.defaults, tt.caseExp)
 
 			// Compare slices
@@ -2479,6 +2481,7 @@ func TestMergeAndDeduplicate(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
 			result := mergeAndDeduplicate(tt.a, tt.b)
 			if !stringSlicesEqual(result, tt.expected) {
 				t.Errorf("got %v, want %v", result, tt.expected)
@@ -2552,6 +2555,7 @@ func TestMergeFileContains(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
 			result := mergeFileContains(tt.a, tt.b)
 			if !fileContainsSlicesEqual(result, tt.expected) {
 				t.Errorf("got %v, want %v", result, tt.expected)
@@ -2560,7 +2564,7 @@ func TestMergeFileContains(t *testing.T) {
 	}
 }
 
-// Helper functions for test comparisons
+// Helper functions for test comparisons.
 func stringSlicesEqual(a, b []string) bool {
 	if len(a) != len(b) {
 		return false

From 6cf5871554c615588c32d90735f6c269378b7871 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 16 Jul 2026 04:06:39 +0000
Subject: [PATCH 7/8] fix: address code review feedback - nil handling and
 redundant checks

---
 internal/evaluator/evaluator.go      | 6 ++++++
 internal/evaluator/evaluator_test.go | 6 ------
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/internal/evaluator/evaluator.go b/internal/evaluator/evaluator.go
index 1a4a1b1c..ba858c59 100644
--- a/internal/evaluator/evaluator.go
+++ b/internal/evaluator/evaluator.go
@@ -818,9 +818,15 @@ func resolveExpectConfig(expectCfg *config.Expect) *config.Expect {
 // file_contains) are appended and de-duplicated. Scalar fields (exit_code,
 // golden_file) are overridden by the case when set.
 func mergeExpectConfig(defaults, caseExpect *config.Expect) config.Expect {
+	if defaults == nil && caseExpect == nil {
+		return config.Expect{}
+	}
 	if defaults == nil {
 		return *caseExpect
 	}
+	if caseExpect == nil {
+		return *defaults
+	}
 
 	merged := config.Expect{}
 
diff --git a/internal/evaluator/evaluator_test.go b/internal/evaluator/evaluator_test.go
index 543437ad..c4124a45 100644
--- a/internal/evaluator/evaluator_test.go
+++ b/internal/evaluator/evaluator_test.go
@@ -2569,9 +2569,6 @@ func stringSlicesEqual(a, b []string) bool {
 	if len(a) != len(b) {
 		return false
 	}
-	if len(a) == 0 && len(b) == 0 {
-		return true
-	}
 	for i := range a {
 		if a[i] != b[i] {
 			return false
@@ -2584,9 +2581,6 @@ func fileContainsSlicesEqual(a, b []config.FileContainsCheck) bool {
 	if len(a) != len(b) {
 		return false
 	}
-	if len(a) == 0 && len(b) == 0 {
-		return true
-	}
 	for i := range a {
 		if a[i].Path != b[i].Path || a[i].Content != b[i].Content {
 			return false

From 4ce503861b31fc5381938bb0a94c8e2c7c9f4444 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 16 Jul 2026 04:08:27 +0000
Subject: [PATCH 8/8] refactor: pass default expect by value instead of pointer

---
 internal/evaluator/evaluator.go | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/internal/evaluator/evaluator.go b/internal/evaluator/evaluator.go
index ba858c59..a013badb 100644
--- a/internal/evaluator/evaluator.go
+++ b/internal/evaluator/evaluator.go
@@ -510,8 +510,8 @@ func (e *defaultEvaluator) runExpectPreCheck(
 	result *EvalResult,
 ) bool {
 	// Merge default expect with case-level expect
-	defaultExpect := &e.evalCfg.Cases.Defaults.Expect
-	mergedExpect := mergeExpectConfig(defaultExpect, &caseCfg.Expect)
+	defaultExpect := e.evalCfg.Cases.Defaults.Expect
+	mergedExpect := mergeExpectConfig(&defaultExpect, &caseCfg.Expect)
 
 	expectCfg := resolveExpectConfig(&mergedExpect)
 	if expectCfg == nil {