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docs/api/ctx.md (1)

524-526: Clarify the AcceptsLanguagesExtended example with a concrete header and expected output

The current example “depends on extended ranges” is ambiguous. Replace it with a concrete Accept-Language header and expected result. Also consider adding a second example for a different wildcard pattern.

Apply this diff:

-  c.AcceptsLanguagesExtended("en-US", "fr-CA")
-  // depends on extended ranges in the request header
+  // Accept-Language: en-*, fr-CA
+  c.AcceptsLanguagesExtended("en-US", "de-DE") // "en-US"

Optional follow-ups (nearby in the same example block):

• Example 2:
  • Header: “Accept-Language: *-US”
  • Call: c.AcceptsLanguagesExtended("en-US", "fr-CA") // "en-US"
• Note invalid patterns:
  • Header: “Accept-Language: en-US-*” → c.AcceptsLanguagesExtended("en-US") // "" (invalid range is rejected)

ctx_test.go (1)

335-349: Refactor to table-driven tests for extended filtering scenarios

The assertions are correct and valuable. For maintainability and extensibility, convert to a table-driven test as previously suggested.

Here’s a table-driven variant:

func Test_Ctx_AcceptsLanguagesExtended(t *testing.T) {
	t.Parallel()
	app := New()
	c := app.AcquireCtx(&fasthttp.RequestCtx{})
	defer app.ReleaseCtx(c)

	testCases := []struct {
		name     string
		header   string
		offers   []string
		expected string
	}{
		{"wildcard suffix matches", "en-*", []string{"en-US"}, "en-US"},
		{"wildcard prefix matches", "*-US", []string{"en-US", "fr-CA"}, "en-US"},
		{"invalid trailing wildcard", "en-US-*", []string{"en-US"}, ""},
	}

	for _, tc := range testCases {
		t.Run(tc.name, func(t *testing.T) {
			c.Request().Header.Set(HeaderAcceptLanguage, tc.header)
			require.Equal(t, tc.expected, c.AcceptsLanguagesExtended(tc.offers...))
		})
	}
}

helpers.go (1)

204-209: Micro-opt: avoid Contains; use IndexByte (duplicate of existing feedback)

Use IndexByte to avoid extra allocs/scans and keep the intent explicit that only the presence of '' matters (spec == "" already handled).

- if strings.Contains(spec, "*") { // only "*" is allowed in Basic
+ if strings.IndexByte(spec, '*') != -1 { // only "*" is allowed in Basic
     return false
 }

helpers_test.go (2)

66-73: Good Basic Filtering coverage; add a couple of edge cases

Looks correct and aligns with RFC 4647 Basic Filtering. Consider adding:

• A positive case for the sole wildcard.
• A negative selection case where a wildcard range is rejected under Basic but a concrete tag is still chosen.

You can extend this block like so:

 require.True(t, acceptsLanguageOfferBasic("EN", "en-us", nil))
 require.False(t, acceptsLanguageOfferBasic("en", "en_US", nil))
 require.Equal(t, "en-US", getOffer([]byte("fr-CA;q=0.8, en-US"), acceptsLanguageOfferBasic, "en-US", "fr-CA"))
 require.Equal(t, "", getOffer([]byte("xx"), acceptsLanguageOfferBasic, "en"))
 require.False(t, acceptsLanguageOfferBasic("en-*", "en-US", nil))
+// sole wildcard should match anything
+require.True(t, acceptsLanguageOfferBasic("*", "en-US", nil))
+// wildcard range is invalid in Basic; ensure negotiation still picks a concrete alternative
+require.Equal(t, "fr-CA", getOffer([]byte("en-*;q=1.0, fr-CA;q=0.8"), acceptsLanguageOfferBasic, "en-US", "fr-CA"))

---

74-79: Extended Filtering tests look solid; add a couple more to pin semantics

These cases validate wildcard-per-subtag and length rules well. Two more helpful assertions:

• en-*-US should match en-Latn-US
• *-US should not match en-Latn-US (position must match)

Suggested additions:

 require.True(t, acceptsLanguageOfferExtended("en-*", "en-US", nil))
 require.True(t, acceptsLanguageOfferExtended("*-US", "en-US", nil))
 require.False(t, acceptsLanguageOfferExtended("en-US-*", "en-US", nil))
 require.Equal(t, "en-US", getOffer([]byte("fr-CA;q=0.8, en-*"), acceptsLanguageOfferExtended, "en-US", "fr-CA"))
+require.True(t, acceptsLanguageOfferExtended("en-*-US", "en-Latn-US", nil))
+require.False(t, acceptsLanguageOfferExtended("*-US", "en-Latn-US", nil))

helpers.go (1)

218-240: Extended Filtering: correct per-subtag wildcard semantics

• Permits wildcard as a full subtag that matches exactly one subtag.
• Requires the offer to have at least as many subtags as the range.
• Allows extra trailing subtags in the offer, which is correct for extended filtering.

Optional micro-optimization: fast-path exact match to skip splits.

 func acceptsLanguageOfferExtended(spec, offer string, _ headerParams) bool {
+    // Fast path for exact case-insensitive match
+    if utils.EqualFold(spec, offer) {
+        return true
+    }
     if spec == "*" {
         return true
     }

Configuration used: CodeRabbit UI
Review profile: CHILL
Plan: Pro

Learnt from: gaby
PR: gofiber/fiber#3193
File: middleware/adaptor/adaptor.go:111-111
Timestamp: 2024-11-10T23:44:13.704Z
Learning: In the `middleware/adaptor/adaptor.go` file of the Fiber framework, when updating context handling, replacing `c.Context()` with `c.RequestCtx()` is appropriate to access the `fasthttp.RequestCtx`.

Learnt from: gaby
PR: gofiber/fiber#3193
File: middleware/cache/cache_test.go:897-897
Timestamp: 2024-11-08T04:10:42.990Z
Learning: In the Fiber framework, `Context()` is being renamed to `RequestCtx()`, and `UserContext()` to `Context()` to improve clarity and align with Go's context conventions.

Learnt from: sixcolors
PR: gofiber/fiber#3016
File: middleware/csrf/csrf_test.go:188-193
Timestamp: 2024-10-08T19:06:06.583Z
Learning: In the Fiber framework tests, using `ctx.Response.Header.Cookie` may not be suitable for parsing cookies from the response header, as it requires a `*Cookie` and fills it rather than returning a string value; thus, manual parsing of the `Set-Cookie` header may be necessary.

Learnt from: ReneWerner87
PR: gofiber/fiber#3161
File: app.go:923-932
Timestamp: 2024-11-15T07:56:21.623Z
Learning: In the Fiber framework, breaking changes are acceptable when moving from version 2 to version 3, including modifications to method signatures such as in the `Test` method in `app.go`.

Learnt from: efectn
PR: gofiber/fiber#3162
File: hooks_test.go:228-228
Timestamp: 2024-12-13T08:14:22.851Z
Learning: In Go test files, prefer using the `require` methods from the `testify` package for assertions instead of manual comparisons and calls to `t.Fatal` or `t.Fatalf`.

Learnt from: sixcolors
PR: gofiber/fiber#2922
File: middleware/cors/utils.go:63-71
Timestamp: 2024-07-26T21:00:12.902Z
Learning: The project uses the testify/assert package for assertions in unit tests.

Learnt from: sixcolors
PR: gofiber/fiber#3016
File: middleware/session/store.go:164-167
Timestamp: 2024-10-08T19:06:06.583Z
Learning: Unit tests in this project use testify require.

Learnt from: efectn
PR: gofiber/fiber#3162
File: app_test.go:893-895
Timestamp: 2024-11-29T12:37:27.581Z
Learning: In the `Test_App_ShutdownWithContext` function in `app_test.go`, the `clientDone` channel is used to synchronize the client's request completion before proceeding, eliminating the need for additional `time.Sleep` calls.

Learnt from: gaby
PR: gofiber/fiber#3170
File: ctx_test.go:1721-1724
Timestamp: 2024-10-16T12:12:30.506Z
Learning: In the Go unit tests in `ctx_test.go`, it is acceptable to use invalid CIDR notation such as `"0.0.0.1/31junk"` for testing purposes.

Learnt from: gaby
PR: gofiber/fiber#3056
File: middleware/encryptcookie/utils.go:22-25
Timestamp: 2024-10-08T19:06:06.583Z
Learning: The `encryptcookie_test.go` file contains unit tests that validate key lengths for both `EncryptCookie` and `DecryptCookie` functions, ensuring that invalid key lengths raise appropriate errors.

Learnt from: sixcolors
PR: gofiber/fiber#3051
File: middleware/session/session.go:215-216
Timestamp: 2024-10-08T19:06:06.583Z
Learning: Parallel tests for `Session.Save` already exist in the `middleware/session/session_test.go` file, specifically in the `Test_Session_Save` and `Test_Session_Save_Expiration` functions.

helpers.go (1)

207-209: Nit: micro-optimization for asterisk detection

After the explicit check for spec == "*", use IndexByte for a tiny perf win and to avoid allocating in Contains.

-	if strings.Contains(spec, "*") { // only "*" is allowed in Basic
+	if strings.IndexByte(spec, '*') != -1 { // only "*" is allowed in Basic
 		return false
 	}

docs/api/ctx.md (1)

525-527: Provide a concrete example for Extended Filtering

“depends on extended ranges in the request header” is vague. Show an actual header and expected result to make usage obvious.

-  c.AcceptsLanguagesExtended("en-US", "fr-CA")
-  // depends on extended ranges in the request header
+  // Accept-Language: en-*, fr-CA
+  c.AcceptsLanguagesExtended("en-US", "de-DE") // "en-US"

ctx_test.go (1)

335-349: Extended filtering tests are correct; consider table-driven expansion

Current cases validate wildcard semantics and the “exactly one subtag” rule. To scale, refactor to a table-driven test and add a few canonical RFC scenarios:

• "de-CH" matches "de-CH-1996"
• "de-*-DE" matches "de-Latn-DE", not "de-DE"
• "*-US" matches "en-US", "es-US" if offered
• "en" matches "en-US" (range shorter than tag is allowed)

Example additional cases:

t.Run("extended_examples", func(t *testing.T) {
  app := New()
  c := app.AcquireCtx(&fasthttp.RequestCtx{})
  defer app.ReleaseCtx(c)

  cases := []struct{
    header string
    offers []string
    want   string
  }{
    {"de-CH", []string{"de-CH-1996", "de"}, "de-CH-1996"},
    {"de-*-DE", []string{"de-Latn-DE", "de-DE"}, "de-Latn-DE"},
    {"*-US", []string{"en-US", "es-US"}, "en-US"},
    {"en", []string{"en-US"}, "en-US"},
  }
  for _, tc := range cases {
    c.Request().Header.Set(HeaderAcceptLanguage, tc.header)
    require.Equal(t, tc.want, c.AcceptsLanguagesExtended(tc.offers...))
  }
})

helpers.go (2)

200-202: Clarify comment: any non-standalone “*” is invalid in Basic

Current wording mentions “after a hyphen”; Basic filtering actually disallows “*” anywhere unless it's the entire range.

-// followed by a hyphen. The comparison is case-insensitive. Only a single "*"
-// as the entire range is allowed. Any "*" appearing after a hyphen renders the
-// range invalid and will not match.
+// followed by a hyphen (case-insensitive). Only a single "*" as the entire
+// range is allowed; any occurrence of "*" in any other position renders the
+// range invalid and will not match.

---

222-240: Extended filtering correctly allows wildcard subtags and extra trailing subtags

• The “at least as many subtags as the range” guard (len(rs) > len(ts) ⇒ false) is correct.
• Wildcard matches exactly one subtag; additional subtags in the offer are allowed, which aligns with RFC 4647 Extended Filtering (e.g., "en-*" matches "en-US-CA").

Consider adding tests that demonstrate:

• "de-CH" matches "de-CH-1996" (extra subtag allowed).
• "de-*-DE" matches "de-Latn-DE" but not "de-DE" (wildcard must match exactly one subtag).

Would you like me to open a follow-up PR adding these tests to helpers/ctx tests?

req.go (1)

59-64: Extended filtering API addition looks good; consider de-dup of header read

The new AcceptsLanguagesExtended maps cleanly to the extended matcher and mirrors the Basic variant. Implementation is solid.

To remove duplication and centralize future changes, consider a small helper:

// outside selected lines, for illustration only
func (r *DefaultReq) acceptsLang(offerFn func(string, string, headerParams) bool, offers ...string) string {
    header := joinHeaderValues(r.Request().Header.PeekAll(HeaderAcceptLanguage))
    return getOffer(header, offerFn, offers...)
}

func (r *DefaultReq) AcceptsLanguages(offers ...string) string {
    return r.acceptsLang(acceptsLanguageOfferBasic, offers...)
}
func (r *DefaultReq) AcceptsLanguagesExtended(offers ...string) string {
    return r.acceptsLang(acceptsLanguageOfferExtended, offers...)
}

helpers_test.go (1)

66-79: Good coverage split between Basic and Extended; add a few edge cases

The tests clearly differentiate RFC 4647 Basic and Extended behavior. Consider adding a couple of small cases to harden coverage:

• Basic: reject other wildcard-subtag forms like "*-US".
• Extended: reject underscore separators.
• Extended: verify q-weight ordering when a wildcard competes with a specific tag.

You can append assertions like:

   // Accept-Language Basic Filtering
   require.True(t, acceptsLanguageOfferBasic("en", "en-US", nil))
   require.False(t, acceptsLanguageOfferBasic("en-US", "en", nil))
   require.True(t, acceptsLanguageOfferBasic("EN", "en-us", nil))
   require.False(t, acceptsLanguageOfferBasic("en", "en_US", nil))
   require.Equal(t, "en-US", getOffer([]byte("fr-CA;q=0.8, en-US"), acceptsLanguageOfferBasic, "en-US", "fr-CA"))
   require.Equal(t, "", getOffer([]byte("xx"), acceptsLanguageOfferBasic, "en"))
   require.False(t, acceptsLanguageOfferBasic("en-*", "en-US", nil))
+  require.False(t, acceptsLanguageOfferBasic("*-US", "en-US", nil))

   // Accept-Language Extended Filtering
   require.True(t, acceptsLanguageOfferExtended("en-*", "en-US", nil))
   require.True(t, acceptsLanguageOfferExtended("*-US", "en-US", nil))
   require.False(t, acceptsLanguageOfferExtended("en-US-*", "en-US", nil))
   require.Equal(t, "en-US", getOffer([]byte("fr-CA;q=0.8, en-*"), acceptsLanguageOfferExtended, "en-US", "fr-CA"))
+  require.False(t, acceptsLanguageOfferExtended("en_*", "en-US", nil))
+  require.Equal(t, "fr-CA", getOffer([]byte("en-*;q=0.5, fr-CA;q=0.9"), acceptsLanguageOfferExtended, "en-US", "fr-CA"))

Configuration used: CodeRabbit UI
Review profile: CHILL
Plan: Pro

Learnt from: ReneWerner87
PR: gofiber/fiber#0
File: :0-0
Timestamp: 2024-12-01T10:28:36.011Z
Learning: Feature request #3224 has been created to add support for square bracket notation and comma-separated values in multipart form data in Fiber, while maintaining binary data transfer capabilities. This would bring parity with the existing form-urlencoded functionality.

Learnt from: gaby
PR: gofiber/fiber#3193
File: middleware/adaptor/adaptor.go:111-111
Timestamp: 2024-11-10T23:44:13.704Z
Learning: In the `middleware/adaptor/adaptor.go` file of the Fiber framework, when updating context handling, replacing `c.Context()` with `c.RequestCtx()` is appropriate to access the `fasthttp.RequestCtx`.

Learnt from: gaby
PR: gofiber/fiber#3193
File: middleware/cache/cache_test.go:897-897
Timestamp: 2024-11-08T04:10:42.990Z
Learning: In the Fiber framework, `Context()` is being renamed to `RequestCtx()`, and `UserContext()` to `Context()` to improve clarity and align with Go's context conventions.

Learnt from: sixcolors
PR: gofiber/fiber#3016
File: middleware/csrf/csrf_test.go:188-193
Timestamp: 2024-10-08T19:06:06.583Z
Learning: In the Fiber framework tests, using `ctx.Response.Header.Cookie` may not be suitable for parsing cookies from the response header, as it requires a `*Cookie` and fills it rather than returning a string value; thus, manual parsing of the `Set-Cookie` header may be necessary.

Learnt from: ReneWerner87
PR: gofiber/fiber#3161
File: app.go:923-932
Timestamp: 2024-11-15T07:56:21.623Z
Learning: In the Fiber framework, breaking changes are acceptable when moving from version 2 to version 3, including modifications to method signatures such as in the `Test` method in `app.go`.

Learnt from: efectn
PR: gofiber/fiber#3162
File: hooks_test.go:228-228
Timestamp: 2024-12-13T08:14:22.851Z
Learning: In Go test files, prefer using the `require` methods from the `testify` package for assertions instead of manual comparisons and calls to `t.Fatal` or `t.Fatalf`.

Learnt from: sixcolors
PR: gofiber/fiber#2922
File: middleware/cors/utils.go:63-71
Timestamp: 2024-07-26T21:00:12.902Z
Learning: The project uses the testify/assert package for assertions in unit tests.

Learnt from: sixcolors
PR: gofiber/fiber#3016
File: middleware/session/store.go:164-167
Timestamp: 2024-10-08T19:06:06.583Z
Learning: Unit tests in this project use testify require.

Learnt from: gaby
PR: gofiber/fiber#3170
File: ctx_test.go:1721-1724
Timestamp: 2024-10-16T12:12:30.506Z
Learning: In the Go unit tests in `ctx_test.go`, it is acceptable to use invalid CIDR notation such as `"0.0.0.1/31junk"` for testing purposes.

Learnt from: gaby
PR: gofiber/fiber#3056
File: middleware/encryptcookie/utils.go:22-25
Timestamp: 2024-10-08T19:06:06.583Z
Learning: The `encryptcookie_test.go` file contains unit tests that validate key lengths for both `EncryptCookie` and `DecryptCookie` functions, ensuring that invalid key lengths raise appropriate errors.

Learnt from: sixcolors
PR: gofiber/fiber#3051
File: middleware/session/session.go:215-216
Timestamp: 2024-10-08T19:06:06.583Z
Learning: Parallel tests for `Session.Save` already exist in the `middleware/session/session_test.go` file, specifically in the `Test_Session_Save` and `Test_Session_Save_Expiration` functions.

Learnt from: gaby
PR: gofiber/fiber#3056
File: middleware/encryptcookie/utils.go:20-23
Timestamp: 2024-10-08T19:06:06.583Z
Learning: Unit tests for key length enforcement in both `EncryptCookie` and `DecryptCookie` functions have been added to ensure robust validation and prevent potential runtime errors.

Learnt from: efectn
PR: gofiber/fiber#3162
File: app_test.go:893-895
Timestamp: 2024-11-29T12:37:27.581Z
Learning: In the `Test_App_ShutdownWithContext` function in `app_test.go`, the `clientDone` channel is used to synchronize the client's request completion before proceeding, eliminating the need for additional `time.Sleep` calls.

Configuration used: CodeRabbit UI
Review profile: CHILL
Plan: Pro

Learnt from: ReneWerner87
PR: gofiber/fiber#0
File: :0-0
Timestamp: 2024-12-01T10:28:36.011Z
Learning: Feature request #3224 has been created to add support for square bracket notation and comma-separated values in multipart form data in Fiber, while maintaining binary data transfer capabilities. This would bring parity with the existing form-urlencoded functionality.

Learnt from: gaby
PR: gofiber/fiber#3170
File: ctx_test.go:1721-1724
Timestamp: 2024-10-16T12:12:30.506Z
Learning: In the Go unit tests in `ctx_test.go`, it is acceptable to use invalid CIDR notation such as `"0.0.0.1/31junk"` for testing purposes.