Files
Mathias Fredriksson 52e73b1343 test(agent/agentcontextconfig): isolate TestContextPartsFromDir from host HOME (#25649)
ContextPartsFromDir scans ~/.coder/skills via DefaultSkillsDir.
On machines with real skills installed, these leaked into test
results. Set HOME/USERPROFILE to temp dirs on the parent test
so subtests run in a clean environment.
2026-05-25 17:59:32 +03:00

579 lines
20 KiB
Go

package agentcontextconfig_test
import (
"os"
"path/filepath"
"strings"
"testing"
"github.com/stretchr/testify/require"
"github.com/coder/coder/v2/agent/agentcontextconfig"
"github.com/coder/coder/v2/codersdk"
)
// filterParts returns only the parts matching the given type.
func filterParts(parts []codersdk.ChatMessagePart, t codersdk.ChatMessagePartType) []codersdk.ChatMessagePart {
var out []codersdk.ChatMessagePart
for _, p := range parts {
if p.Type == t {
out = append(out, p)
}
}
return out
}
func writeSkillMetaFileInRoot(t *testing.T, skillsRoot, name, description string) string {
t.Helper()
skillDir := filepath.Join(skillsRoot, name)
require.NoError(t, os.MkdirAll(skillDir, 0o755))
require.NoError(t, os.WriteFile(
filepath.Join(skillDir, "SKILL.md"),
[]byte("---\nname: "+name+"\ndescription: "+description+"\n---\nSkill body"),
0o600,
))
return skillDir
}
func writeSkillMetaFile(t *testing.T, dir, name, description string) string {
t.Helper()
return writeSkillMetaFileInRoot(t, filepath.Join(dir, ".agents", "skills"), name, description)
}
//nolint:paralleltest,tparallel // Uses t.Setenv to isolate HOME.
func TestContextPartsFromDir(t *testing.T) {
// Prevent ~/.coder/skills on the host from leaking into results.
t.Setenv("HOME", t.TempDir())
t.Setenv("USERPROFILE", t.TempDir())
t.Run("ReturnsInstructionFilePart", func(t *testing.T) {
t.Parallel()
dir := t.TempDir()
instructionPath := filepath.Join(dir, "AGENTS.md")
require.NoError(t, os.WriteFile(instructionPath, []byte("project instructions"), 0o600))
parts := agentcontextconfig.ContextPartsFromDir(dir)
contextParts := filterParts(parts, codersdk.ChatMessagePartTypeContextFile)
skillParts := filterParts(parts, codersdk.ChatMessagePartTypeSkill)
require.Len(t, parts, 1)
require.Len(t, contextParts, 1)
require.Empty(t, skillParts)
require.Equal(t, instructionPath, contextParts[0].ContextFilePath)
require.Equal(t, "project instructions", contextParts[0].ContextFileContent)
require.False(t, contextParts[0].ContextFileTruncated)
})
t.Run("ReturnsSkillParts", func(t *testing.T) {
t.Parallel()
dir := t.TempDir()
skillDir := writeSkillMetaFile(t, dir, "my-skill", "A test skill")
parts := agentcontextconfig.ContextPartsFromDir(dir)
contextParts := filterParts(parts, codersdk.ChatMessagePartTypeContextFile)
skillParts := filterParts(parts, codersdk.ChatMessagePartTypeSkill)
require.Len(t, parts, 1)
require.Empty(t, contextParts)
require.Len(t, skillParts, 1)
require.Equal(t, "my-skill", skillParts[0].SkillName)
require.Equal(t, "A test skill", skillParts[0].SkillDescription)
require.Equal(t, skillDir, skillParts[0].SkillDir)
require.Equal(t, "SKILL.md", skillParts[0].ContextFileSkillMetaFile)
})
t.Run("ReturnsSkillPartsFromSkillsDir", func(t *testing.T) {
t.Parallel()
dir := t.TempDir()
skillDir := writeSkillMetaFileInRoot(
t,
filepath.Join(dir, "skills"),
"my-skill",
"A test skill",
)
parts := agentcontextconfig.ContextPartsFromDir(dir)
contextParts := filterParts(parts, codersdk.ChatMessagePartTypeContextFile)
skillParts := filterParts(parts, codersdk.ChatMessagePartTypeSkill)
require.Len(t, parts, 1)
require.Empty(t, contextParts)
require.Len(t, skillParts, 1)
require.Equal(t, "my-skill", skillParts[0].SkillName)
require.Equal(t, "A test skill", skillParts[0].SkillDescription)
require.Equal(t, skillDir, skillParts[0].SkillDir)
require.Equal(t, "SKILL.md", skillParts[0].ContextFileSkillMetaFile)
})
t.Run("ReturnsEmptyForEmptyDir", func(t *testing.T) {
t.Parallel()
parts := agentcontextconfig.ContextPartsFromDir(t.TempDir())
require.NotNil(t, parts)
require.Empty(t, parts)
})
t.Run("ReturnsCombinedResults", func(t *testing.T) {
t.Parallel()
dir := t.TempDir()
instructionPath := filepath.Join(dir, "AGENTS.md")
require.NoError(t, os.WriteFile(instructionPath, []byte("combined instructions"), 0o600))
skillDir := writeSkillMetaFile(t, dir, "combined-skill", "Combined test skill")
parts := agentcontextconfig.ContextPartsFromDir(dir)
contextParts := filterParts(parts, codersdk.ChatMessagePartTypeContextFile)
skillParts := filterParts(parts, codersdk.ChatMessagePartTypeSkill)
require.Len(t, parts, 2)
require.Len(t, contextParts, 1)
require.Len(t, skillParts, 1)
require.Equal(t, instructionPath, contextParts[0].ContextFilePath)
require.Equal(t, "combined instructions", contextParts[0].ContextFileContent)
require.Equal(t, "combined-skill", skillParts[0].SkillName)
require.Equal(t, skillDir, skillParts[0].SkillDir)
})
}
func setupConfigTestEnv(t *testing.T, overrides map[string]string) string {
t.Helper()
fakeHome := t.TempDir()
t.Setenv("HOME", fakeHome)
t.Setenv("USERPROFILE", fakeHome)
t.Setenv(agentcontextconfig.EnvInstructionsDirs, "")
t.Setenv(agentcontextconfig.EnvInstructionsFile, "")
t.Setenv(agentcontextconfig.EnvSkillsDirs, "")
t.Setenv(agentcontextconfig.EnvSkillMetaFile, "")
t.Setenv(agentcontextconfig.EnvMCPConfigFiles, "")
for key, value := range overrides {
t.Setenv(key, value)
}
return fakeHome
}
func TestResolve(t *testing.T) {
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
t.Run("Defaults", func(t *testing.T) {
setupConfigTestEnv(t, nil)
workDir := platformAbsPath("work")
cfg, mcpFiles := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
// Parts is always non-nil.
require.NotNil(t, cfg.Parts)
// Default MCP config file is ".mcp.json" (relative),
// resolved against the working directory.
require.Equal(t, []string{filepath.Join(workDir, ".mcp.json")}, mcpFiles)
})
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
t.Run("CustomEnvVars", func(t *testing.T) {
optInstructions := t.TempDir()
optSkills := t.TempDir()
optMCP := platformAbsPath("opt", "mcp.json")
setupConfigTestEnv(t, map[string]string{
agentcontextconfig.EnvInstructionsDirs: optInstructions,
agentcontextconfig.EnvInstructionsFile: "CUSTOM.md",
agentcontextconfig.EnvSkillsDirs: optSkills,
agentcontextconfig.EnvSkillMetaFile: "META.yaml",
agentcontextconfig.EnvMCPConfigFiles: optMCP,
})
// Create files matching the custom names so we can
// verify the env vars actually change lookup behavior.
require.NoError(t, os.WriteFile(filepath.Join(optInstructions, "CUSTOM.md"), []byte("custom instructions"), 0o600))
skillDir := filepath.Join(optSkills, "my-skill")
require.NoError(t, os.MkdirAll(skillDir, 0o755))
require.NoError(t, os.WriteFile(
filepath.Join(skillDir, "META.yaml"),
[]byte("---\nname: my-skill\ndescription: custom meta\n---\n"),
0o600,
))
workDir := platformAbsPath("work")
cfg, mcpFiles := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
require.Equal(t, []string{optMCP}, mcpFiles)
ctxFiles := filterParts(cfg.Parts, codersdk.ChatMessagePartTypeContextFile)
require.Len(t, ctxFiles, 1)
require.Equal(t, "custom instructions", ctxFiles[0].ContextFileContent)
skillParts := filterParts(cfg.Parts, codersdk.ChatMessagePartTypeSkill)
require.Len(t, skillParts, 1)
require.Equal(t, "my-skill", skillParts[0].SkillName)
require.Equal(t, "META.yaml", skillParts[0].ContextFileSkillMetaFile)
})
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
t.Run("WhitespaceInFileNames", func(t *testing.T) {
fakeHome := setupConfigTestEnv(t, map[string]string{
agentcontextconfig.EnvInstructionsFile: " CLAUDE.md ",
})
t.Setenv(agentcontextconfig.EnvInstructionsDirs, fakeHome)
workDir := t.TempDir()
// Create a file matching the trimmed name.
require.NoError(t, os.WriteFile(filepath.Join(fakeHome, "CLAUDE.md"), []byte("hello"), 0o600))
cfg, _ := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
ctxFiles := filterParts(cfg.Parts, codersdk.ChatMessagePartTypeContextFile)
require.Len(t, ctxFiles, 1)
require.Equal(t, "hello", ctxFiles[0].ContextFileContent)
})
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
t.Run("CommaSeparatedDirs", func(t *testing.T) {
a := t.TempDir()
b := t.TempDir()
setupConfigTestEnv(t, map[string]string{
agentcontextconfig.EnvInstructionsDirs: a + "," + b,
})
// Put instruction files in both dirs.
require.NoError(t, os.WriteFile(filepath.Join(a, "AGENTS.md"), []byte("from a"), 0o600))
require.NoError(t, os.WriteFile(filepath.Join(b, "AGENTS.md"), []byte("from b"), 0o600))
workDir := t.TempDir()
cfg, _ := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
ctxFiles := filterParts(cfg.Parts, codersdk.ChatMessagePartTypeContextFile)
require.Len(t, ctxFiles, 2)
require.Equal(t, "from a", ctxFiles[0].ContextFileContent)
require.Equal(t, "from b", ctxFiles[1].ContextFileContent)
})
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
t.Run("ReadsInstructionFiles", func(t *testing.T) {
workDir := t.TempDir()
fakeHome := setupConfigTestEnv(t, nil)
// Create ~/.coder/AGENTS.md
coderDir := filepath.Join(fakeHome, ".coder")
require.NoError(t, os.MkdirAll(coderDir, 0o755))
require.NoError(t, os.WriteFile(
filepath.Join(coderDir, "AGENTS.md"),
[]byte("home instructions"),
0o600,
))
cfg, _ := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
ctxFiles := filterParts(cfg.Parts, codersdk.ChatMessagePartTypeContextFile)
require.NotNil(t, cfg.Parts)
require.Len(t, ctxFiles, 1)
require.Equal(t, "home instructions", ctxFiles[0].ContextFileContent)
require.Equal(t, filepath.Join(coderDir, "AGENTS.md"), ctxFiles[0].ContextFilePath)
require.False(t, ctxFiles[0].ContextFileTruncated)
})
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
t.Run("ReadsWorkingDirInstructionFile", func(t *testing.T) {
setupConfigTestEnv(t, nil)
workDir := t.TempDir()
// Create AGENTS.md in the working directory.
require.NoError(t, os.WriteFile(
filepath.Join(workDir, "AGENTS.md"),
[]byte("project instructions"),
0o600,
))
cfg, _ := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
// Should find the working dir file (not in instruction dirs).
ctxFiles := filterParts(cfg.Parts, codersdk.ChatMessagePartTypeContextFile)
require.NotNil(t, cfg.Parts)
require.Len(t, ctxFiles, 1)
require.Equal(t, "project instructions", ctxFiles[0].ContextFileContent)
require.Equal(t, filepath.Join(workDir, "AGENTS.md"), ctxFiles[0].ContextFilePath)
})
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
t.Run("TruncatesLargeInstructionFile", func(t *testing.T) {
setupConfigTestEnv(t, nil)
workDir := t.TempDir()
largeContent := strings.Repeat("a", 64*1024+100)
require.NoError(t, os.WriteFile(filepath.Join(workDir, "AGENTS.md"), []byte(largeContent), 0o600))
cfg, _ := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
ctxFiles := filterParts(cfg.Parts, codersdk.ChatMessagePartTypeContextFile)
require.Len(t, ctxFiles, 1)
require.True(t, ctxFiles[0].ContextFileTruncated)
require.Len(t, ctxFiles[0].ContextFileContent, 64*1024)
})
sanitizationTests := []struct {
name string
input string
expected string
}{
{
name: "SanitizesHTMLComments",
input: "visible\n<!-- hidden -->content",
expected: "visible\ncontent",
},
{
name: "SanitizesInvisibleUnicode",
input: "before\u200bafter",
expected: "beforeafter",
},
{
name: "NormalizesCRLF",
input: "line1\r\nline2\rline3",
expected: "line1\nline2\nline3",
},
}
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
for _, tt := range sanitizationTests {
t.Run(tt.name, func(t *testing.T) {
setupConfigTestEnv(t, nil)
workDir := t.TempDir()
require.NoError(t, os.WriteFile(
filepath.Join(workDir, "AGENTS.md"),
[]byte(tt.input),
0o600,
))
cfg, _ := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
ctxFiles := filterParts(cfg.Parts, codersdk.ChatMessagePartTypeContextFile)
require.Len(t, ctxFiles, 1)
require.Equal(t, tt.expected, ctxFiles[0].ContextFileContent)
})
}
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
t.Run("DiscoversSkills", func(t *testing.T) {
fakeHome := t.TempDir()
t.Setenv("HOME", fakeHome)
t.Setenv("USERPROFILE", fakeHome)
t.Setenv(agentcontextconfig.EnvInstructionsDirs, fakeHome)
t.Setenv(agentcontextconfig.EnvInstructionsFile, "")
t.Setenv(agentcontextconfig.EnvSkillMetaFile, "")
t.Setenv(agentcontextconfig.EnvMCPConfigFiles, "")
workDir := t.TempDir()
skillsDir := filepath.Join(workDir, ".agents", "skills")
t.Setenv(agentcontextconfig.EnvSkillsDirs, skillsDir)
// Create a valid skill.
skillDir := filepath.Join(skillsDir, "my-skill")
require.NoError(t, os.MkdirAll(skillDir, 0o755))
require.NoError(t, os.WriteFile(
filepath.Join(skillDir, "SKILL.md"),
[]byte("---\nname: my-skill\ndescription: A test skill\n---\nSkill body"),
0o600,
))
cfg, _ := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
skillParts := filterParts(cfg.Parts, codersdk.ChatMessagePartTypeSkill)
require.Len(t, skillParts, 1)
require.Equal(t, "my-skill", skillParts[0].SkillName)
require.Equal(t, "A test skill", skillParts[0].SkillDescription)
require.Equal(t, skillDir, skillParts[0].SkillDir)
require.Equal(t, "SKILL.md", skillParts[0].ContextFileSkillMetaFile)
})
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
t.Run("SkipsMissingDirs", func(t *testing.T) {
nonExistent := filepath.Join(t.TempDir(), "does-not-exist")
setupConfigTestEnv(t, map[string]string{
agentcontextconfig.EnvInstructionsDirs: nonExistent,
agentcontextconfig.EnvSkillsDirs: nonExistent,
})
workDir := t.TempDir()
cfg, _ := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
// Non-nil empty slice (signals agent supports new format).
require.NotNil(t, cfg.Parts)
require.Empty(t, cfg.Parts)
})
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
t.Run("MCPConfigFilesResolvedSeparately", func(t *testing.T) {
optMCP := platformAbsPath("opt", "custom.json")
fakeHome := setupConfigTestEnv(t, map[string]string{
agentcontextconfig.EnvMCPConfigFiles: optMCP,
})
t.Setenv(agentcontextconfig.EnvInstructionsDirs, fakeHome)
workDir := t.TempDir()
_, mcpFiles := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
require.Equal(t, []string{optMCP}, mcpFiles)
})
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
t.Run("SkillNameMustMatchDir", func(t *testing.T) {
fakeHome := setupConfigTestEnv(t, nil)
t.Setenv(agentcontextconfig.EnvInstructionsDirs, fakeHome)
workDir := t.TempDir()
skillsDir := filepath.Join(workDir, "skills")
t.Setenv(agentcontextconfig.EnvSkillsDirs, skillsDir)
// Skill name in frontmatter doesn't match directory name.
skillDir := filepath.Join(skillsDir, "wrong-dir-name")
require.NoError(t, os.MkdirAll(skillDir, 0o755))
require.NoError(t, os.WriteFile(
filepath.Join(skillDir, "SKILL.md"),
[]byte("---\nname: actual-name\ndescription: mismatch\n---\n"),
0o600,
))
cfg, _ := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
skillParts := filterParts(cfg.Parts, codersdk.ChatMessagePartTypeSkill)
require.Empty(t, skillParts)
})
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
t.Run("DuplicateSkillsFirstWins", func(t *testing.T) {
fakeHome := setupConfigTestEnv(t, nil)
t.Setenv(agentcontextconfig.EnvInstructionsDirs, fakeHome)
workDir := t.TempDir()
skillsDir1 := filepath.Join(workDir, "skills1")
skillsDir2 := filepath.Join(workDir, "skills2")
t.Setenv(agentcontextconfig.EnvSkillsDirs, skillsDir1+","+skillsDir2)
// Same skill name in both directories.
for _, dir := range []string{skillsDir1, skillsDir2} {
skillDir := filepath.Join(dir, "dup-skill")
require.NoError(t, os.MkdirAll(skillDir, 0o755))
require.NoError(t, os.WriteFile(
filepath.Join(skillDir, "SKILL.md"),
[]byte("---\nname: dup-skill\ndescription: from "+filepath.Base(dir)+"\n---\n"),
0o600,
))
}
cfg, _ := agentcontextconfig.Resolve(workDir, agentcontextconfig.ReadEnvConfig())
skillParts := filterParts(cfg.Parts, codersdk.ChatMessagePartTypeSkill)
require.Len(t, skillParts, 1)
require.Equal(t, "from skills1", skillParts[0].SkillDescription)
})
//nolint:paralleltest // Uses t.Setenv to mutate HOME.
t.Run("DefaultDiscoversHomeAndProjectSkillsHomeWins", func(t *testing.T) {
fakeHome := t.TempDir()
t.Setenv("HOME", fakeHome)
t.Setenv("USERPROFILE", fakeHome)
workDir := t.TempDir()
homeSkills := filepath.Join(fakeHome, ".coder", "skills")
writeSkillMetaFileInRoot(t, homeSkills, "home-only", "home only")
writeSkillMetaFileInRoot(t, homeSkills, "shared", "from home")
writeSkillMetaFile(t, workDir, "project-only", "project only")
writeSkillMetaFile(t, workDir, "shared", "from project")
// Construct the Config directly with the package defaults
// to verify the default skills list (and only the defaults).
cfg, _ := agentcontextconfig.Resolve(workDir, agentcontextconfig.Config{
SkillsDirs: agentcontextconfig.DefaultSkillsDir,
SkillMetaFile: agentcontextconfig.DefaultSkillMetaFile,
})
got := map[string]string{}
for _, p := range filterParts(cfg.Parts, codersdk.ChatMessagePartTypeSkill) {
got[p.SkillName] = p.SkillDescription
}
require.Equal(t, map[string]string{
"home-only": "home only",
"project-only": "project only",
"shared": "from home",
}, got)
})
}
func TestNewAPI_LazyDirectory(t *testing.T) {
t.Setenv(agentcontextconfig.EnvInstructionsDirs, "")
t.Setenv(agentcontextconfig.EnvInstructionsFile, "")
t.Setenv(agentcontextconfig.EnvSkillsDirs, "")
t.Setenv(agentcontextconfig.EnvSkillMetaFile, "")
t.Setenv(agentcontextconfig.EnvMCPConfigFiles, "")
dir := ""
api := agentcontextconfig.NewAPI(func() string { return dir }, agentcontextconfig.ReadEnvConfig())
// Before directory is set, MCP paths resolve to nothing.
mcpFiles := api.MCPConfigFiles()
require.Empty(t, mcpFiles)
// After setting the directory, MCPConfigFiles() picks it up.
dir = platformAbsPath("work")
mcpFiles = api.MCPConfigFiles()
require.NotEmpty(t, mcpFiles)
require.Equal(t, []string{filepath.Join(dir, ".mcp.json")}, mcpFiles)
}
// TestClearEnvVars verifies that ClearEnvVars removes every
// CODER_AGENT_EXP_* env var from the process.
//
//nolint:paralleltest // Mutates process-wide environment.
func TestClearEnvVars(t *testing.T) {
// Set every context config env var.
for _, key := range []string{
agentcontextconfig.EnvInstructionsDirs,
agentcontextconfig.EnvInstructionsFile,
agentcontextconfig.EnvSkillsDirs,
agentcontextconfig.EnvSkillMetaFile,
agentcontextconfig.EnvMCPConfigFiles,
} {
t.Setenv(key, "some-value")
}
agentcontextconfig.ClearEnvVars()
// Every env var should be absent.
for _, key := range []string{
agentcontextconfig.EnvInstructionsDirs,
agentcontextconfig.EnvInstructionsFile,
agentcontextconfig.EnvSkillsDirs,
agentcontextconfig.EnvSkillMetaFile,
agentcontextconfig.EnvMCPConfigFiles,
} {
_, ok := os.LookupEnv(key)
require.False(t, ok, "env var %s should be cleared", key)
}
}
// TestResolve_ConfigOverridesEnv verifies that Resolve uses
// the Config struct, not environment variables.
//
//nolint:paralleltest // Uses t.Setenv to mutate process-wide environment.
func TestResolve_ConfigOverridesEnv(t *testing.T) {
// Set env vars to one value.
envDir := t.TempDir()
t.Setenv(agentcontextconfig.EnvInstructionsDirs, envDir)
// Build a Config with a different value.
cfgDir := t.TempDir()
require.NoError(t, os.WriteFile(
filepath.Join(cfgDir, "AGENTS.md"),
[]byte("from config"),
0o600,
))
cfg := agentcontextconfig.ReadEnvConfig()
cfg.InstructionsDirs = cfgDir
workDir := t.TempDir()
result, _ := agentcontextconfig.Resolve(workDir, cfg)
ctxFiles := filterParts(result.Parts, codersdk.ChatMessagePartTypeContextFile)
require.Len(t, ctxFiles, 1)
require.Equal(t, "from config", ctxFiles[0].ContextFileContent)
}