Remove the code nothing in production calls (closes #312)

Service.Warm, the ImageCache interface, both GenerateSignedURL methods,
signature.ParseParams, imagerequest.ParseImagePath, four symbols of
internal/magic, the image processor's lists of supported formats,
IsEmpty and Count of the allowlist, ssrfSafeDialer, CacheStale,
ErrCacheMiss, ErrNegativeCache, ImageResponse.LastModified and the Load
methods of ContentStorage and VariantStorage had no caller outside
tests. They are gone, with the tests that tested only them.

The handlers tests sign their image URLs with generateSignedURL, a test
helper that builds the URL as the removed generator did. The SSRF dialer
tests call dialSSRFSafe with no operator blocklist, which is all
ssrfSafeDialer did. The tests of ParseImagePath and ContentStorage.Load
call ParseImageURL and LoadWithSize instead. MIMEToImageFormat,
ContentStorage.Store and CleanExpired stay, as pixa calls them.

Model: opus-5-5

internal/magic/magic_internal_test.go

@@ -3,9 +3,6 @@ package magic
 import (
 	"bytes"
 	"errors"
-	"io"
-	"slices"
-	"strings"
 	"testing"
 )
 
@@ -155,119 +152,6 @@ func TestValidateMagicBytes(t *testing.T) {
 	}
 }
 
-func TestIsSupportedMIMEType(t *testing.T) {
-	t.Parallel()
-
-	tests := []struct {
-		mimeType string
-		want     bool
-	}{
-		{testMIMEJPEG, true},
-		{testMIMEPNG, true},
-		{testMIMEWebP, true},
-		{testMIMEGIF, true},
-		{testMIMEAVIF, true},
-		{"image/svg+xml", true},
-		{"IMAGE/JPEG", true},
-		{testMIMEJPEGParams, true},
-		{"image/tiff", false},
-		{"image/bmp", false},
-		{mimeOctetStream, false},
-		{"text/plain", false},
-		{"", false},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.mimeType, func(t *testing.T) {
-			t.Parallel()
-
-			if got := IsSupportedMIMEType(tt.mimeType); got != tt.want {
-				t.Errorf("IsSupportedMIMEType(%q) = %v, want %v", tt.mimeType, got, tt.want)
-			}
-		})
-	}
-}
-
-func TestPeekAndValidate(t *testing.T) {
-	t.Parallel()
-
-	jpegMagic := []byte{
-		0xFF, 0xD8, 0xFF, 0xE0, 0x00, 0x10, 0x4A, 0x46, 0x49, 0x46, 0x00, 0x01,
-	}
-	pngMagic := []byte{
-		0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A, 0x00, 0x00, 0x00, 0x0D,
-	}
-	jpegData := slices.Concat(jpegMagic, []byte("rest of jpeg data"))
-	pngData := slices.Concat(pngMagic, []byte("rest of png data"))
-
-	tests := []struct {
-		name         string
-		data         []byte
-		declaredType string
-		wantErr      bool
-		wantData     []byte
-	}{
-		{
-			name:         "valid JPEG",
-			data:         jpegData,
-			declaredType: testMIMEJPEG,
-			wantErr:      false,
-			wantData:     jpegData,
-		},
-		{
-			name:         "valid PNG",
-			data:         pngData,
-			declaredType: testMIMEPNG,
-			wantErr:      false,
-			wantData:     pngData,
-		},
-		{
-			name:         "mismatched type",
-			data:         jpegData,
-			declaredType: testMIMEPNG,
-			wantErr:      true,
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			t.Parallel()
-
-			r := bytes.NewReader(tt.data)
-
-			result, err := PeekAndValidate(r, tt.declaredType)
-			if tt.wantErr {
-				if err == nil {
-					t.Error("PeekAndValidate() expected error, got nil")
-				}
-
-				return
-			}
-
-			if err != nil {
-				t.Errorf("PeekAndValidate() unexpected error = %v", err)
-
-				return
-			}
-
-			// Read all data from result reader
-			got, err := io.ReadAll(result)
-			if err != nil {
-				t.Errorf("Failed to read result: %v", err)
-
-				return
-			}
-
-			if !bytes.Equal(got, tt.wantData) {
-				t.Errorf(
-					"PeekAndValidate() data mismatch: got %d bytes, want %d bytes",
-					len(got), len(tt.wantData),
-				)
-			}
-		})
-	}
-}
-
 func TestMIMEToImageFormat(t *testing.T) {
 	t.Parallel()
 
@@ -303,35 +187,6 @@ func TestMIMEToImageFormat(t *testing.T) {
 	}
 }
 
-func TestImageFormatToMIME(t *testing.T) {
-	t.Parallel()
-
-	tests := []struct {
-		format   ImageFormat
-		wantMIME string
-	}{
-		{FormatJPEG, testMIMEJPEG},
-		{FormatPNG, testMIMEPNG},
-		{FormatWebP, testMIMEWebP},
-		{FormatGIF, testMIMEGIF},
-		{FormatAVIF, testMIMEAVIF},
-		{FormatOriginal, mimeOctetStream},
-		{"unknown", mimeOctetStream},
-	}
-
-	for _, tt := range tests {
-		t.Run(string(tt.format), func(t *testing.T) {
-			t.Parallel()
-
-			got := ImageFormatToMIME(tt.format)
-
-			if got != tt.wantMIME {
-				t.Errorf("ImageFormatToMIME(%q) = %v, want %v", tt.format, got, tt.wantMIME)
-			}
-		})
-	}
-}
-
 func TestNormalizeMIMEType(t *testing.T) {
 	t.Parallel()
 
@@ -493,34 +348,3 @@ func TestDetectFormatFtypNotAVIF(t *testing.T) {
 		t.Errorf("DetectFormat(MP4) error = %v, want %v", err, ErrUnknownFormat)
 	}
 }
-
-func TestPeekAndValidatePreservesReader(t *testing.T) {
-	t.Parallel()
-
-	// Ensure that after PeekAndValidate, we can read the complete
-	// original content
-	originalContent := append(
-		[]byte{0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A, 0x00, 0x00, 0x00, 0x0D},
-		[]byte(strings.Repeat("PNG IDAT chunk data here ", 100))...,
-	)
-
-	r := bytes.NewReader(originalContent)
-
-	validated, err := PeekAndValidate(r, testMIMEPNG)
-	if err != nil {
-		t.Fatalf("PeekAndValidate() error = %v", err)
-	}
-
-	// Read everything from the validated reader
-	got, err := io.ReadAll(validated)
-	if err != nil {
-		t.Fatalf("io.ReadAll() error = %v", err)
-	}
-
-	if !bytes.Equal(got, originalContent) {
-		t.Errorf(
-			"Content mismatch: got %d bytes, want %d bytes",
-			len(got), len(originalContent),
-		)
-	}
-}