test: add context strategy goldens

docs/context-engine-strategies.md

@@ -16,7 +16,7 @@ Context Engine 的目标不是伪装网页聊天记录，而是把 API 会话编
 
 | strategy | 输出形态 | 默认使用 | 适用场景 | 回滚价值 |
 |---|---|---:|---|---|
-| `raw_transcript` | 旧式 `# DS2API_HISTORY.txt` + `=== N. ROLE ===` transcript | 否 | 调试、回归、兼容旧行为 | 最高，保留旧形态 |
+| `raw_transcript` | 中性标题 + `=== N. ROLE ===` transcript | 否 | 调试、回归、兼容旧行为 | 较高，保留旧式轮次形态 |
 | `natural_context` | `# Conversation Context` + 全量自然化轮次 | 否 | 需要完整历史但不想暴露实现术语 | 从压缩策略回退到全文 |
 | `context_capsule` | 当前任务 + 约束 + 早期摘要，不回放最近完整轮次 | 否 | 普通问答、长历史摘要 | 降低上下文体积 |
 | `hybrid_recent` | 当前任务 + 约束 + 早期摘要 + 最近精确上下文 | 是 | Agent 长任务、编程、调试 | 默认生产策略 |

internal/httpapi/openai/history_split_test.go

@@ -95,7 +95,7 @@ func TestBuildOpenAICurrentInputContextTranscriptUsesNaturalContextSections(t *t
 func TestBuildOpenAICurrentInputContextTranscriptRawStrategy(t *testing.T) {
 	transcript := promptcompat.BuildOpenAICurrentInputContextTranscriptWithStrategy(historySplitTestMessages(), "raw_transcript")
 	for _, want := range []string{
-		"# DS2API_HISTORY.txt",
+		"# Conversation Transcript",
 		"=== 1. SYSTEM ===",
 		"=== 5. USER ===",
 	} {

internal/promptcompat/history_transcript.go

@@ -7,7 +7,7 @@ import (
 
 const CurrentInputContextFilename = "DS2API_HISTORY.txt"
 
-const historyTranscriptTitle = "# DS2API_HISTORY.txt"
+const historyTranscriptTitle = "# Conversation Transcript"
 const historyTranscriptSummary = "Prior conversation history and tool progress."
 const naturalContextTitle = "# Conversation Context"
 const naturalContextSummary = "This note captures the working conversation state for the current request."

internal/promptcompat/history_transcript_test.go

@@ -2,6 +2,8 @@ package promptcompat
 
 import (
 	"fmt"
+	"os"
+	"path/filepath"
 	"strings"
 	"testing"
 )
@@ -46,9 +48,12 @@ func TestBuildOpenAICurrentInputContextTranscriptStrategyShapes(t *testing.T) {
 	}
 
 	raw := BuildOpenAICurrentInputContextTranscriptWithStrategy(messages, "raw_transcript")
-	if !strings.Contains(raw, "# DS2API_HISTORY.txt") || !strings.Contains(raw, "=== 1. SYSTEM ===") {
+	if !strings.Contains(raw, "# Conversation Transcript") || !strings.Contains(raw, "=== 1. SYSTEM ===") {
 		t.Fatalf("expected raw transcript shape, got %q", raw)
 	}
+	if strings.Contains(raw, "DS2API") {
+		t.Fatalf("raw transcript should not expose implementation terms, got %q", raw)
+	}
 
 	natural := BuildOpenAICurrentInputContextTranscriptWithStrategy(messages, "natural_context")
 	if !strings.Contains(natural, "## Conversation") || strings.Contains(natural, "Earlier Context Summary") {
@@ -60,3 +65,26 @@ func TestBuildOpenAICurrentInputContextTranscriptStrategyShapes(t *testing.T) {
 		t.Fatalf("expected context capsule without recent exact section, got %q", capsule)
 	}
 }
+
+func TestBuildOpenAICurrentInputContextTranscriptStrategyGoldens(t *testing.T) {
+	messages := []any{
+		map[string]any{"role": "system", "content": "system rule"},
+		map[string]any{"role": "user", "content": "first turn"},
+		map[string]any{"role": "assistant", "content": "first answer"},
+		map[string]any{"role": "user", "content": "latest request"},
+	}
+	for _, strategy := range []string{"raw_transcript", "natural_context", "context_capsule", "hybrid_recent"} {
+		t.Run(strategy, func(t *testing.T) {
+			got := BuildOpenAICurrentInputContextTranscriptWithStrategy(messages, strategy)
+			path := filepath.Join("testdata", "context_strategy", strategy+".golden")
+			want, err := os.ReadFile(path)
+			if err != nil {
+				t.Fatalf("read golden: %v", err)
+			}
+			wantText := strings.ReplaceAll(string(want), "\r\n", "\n")
+			if got != wantText {
+				t.Fatalf("golden mismatch for %s\n--- got ---\n%s\n--- want ---\n%s", strategy, got, wantText)
+			}
+		})
+	}
+}

internal/promptcompat/testdata/context_strategy/context_capsule.golden

@@ -0,0 +1,15 @@
+# Conversation Context
+This note summarizes earlier context and preserves the most recent turns needed for the current reply.
+
+## Current Task
+latest request
+
+## Non-Negotiable Instructions
+
+- system rule
+
+## Earlier Context Summary
+
+- User: first turn
+- Assistant: first answer
+- User: latest request

internal/promptcompat/testdata/context_strategy/hybrid_recent.golden

@@ -0,0 +1,23 @@
+# Conversation Context
+This note summarizes earlier context and preserves the most recent turns needed for the current reply.
+
+## Current Task
+latest request
+
+## Non-Negotiable Instructions
+
+- system rule
+
+## Recent Exact Context
+
+1. System guidance:
+system rule
+
+2. User:
+first turn
+
+3. Assistant:
+first answer
+
+4. User:
+latest request

internal/promptcompat/testdata/context_strategy/natural_context.golden

@@ -0,0 +1,16 @@
+# Conversation Context
+This note captures the working conversation state for the current request.
+
+## Conversation
+
+1. System guidance:
+system rule
+
+2. User:
+first turn
+
+3. Assistant:
+first answer
+
+4. User:
+latest request

internal/promptcompat/testdata/context_strategy/raw_transcript.golden

@@ -0,0 +1,14 @@
+# Conversation Transcript
+Prior conversation history and tool progress.
+
+=== 1. SYSTEM ===
+system rule
+
+=== 2. USER ===
+first turn
+
+=== 3. ASSISTANT ===
+first answer
+
+=== 4. USER ===
+latest request