Revert "caddyfile: Reject long heredoc markers (#6098)" (#6100)

This reverts commit e7a534d0a3.

caddyconfig/caddyfile/formatter.go

@@ -16,7 +16,6 @@ package caddyfile
 
 import (
 	"bytes"
-	"fmt"
 	"io"
 	"unicode"
 
@@ -119,10 +118,6 @@ func Format(input []byte) []byte {
 				heredoc = heredocClosed
 			} else {
 				heredocMarker = append(heredocMarker, ch)
-				if len(heredocMarker) > 32 {
-					errorString := fmt.Sprintf("heredoc marker too long: <<%s", string(heredocMarker))
-					panic(errorString)
-				}
 				write(ch)
 				continue
 			}

caddyconfig/caddyfile/formatter_test.go

@@ -15,8 +15,6 @@
 package caddyfile
 
 import (
-	"fmt"
-	"os"
 	"strings"
 	"testing"
 )
@@ -26,7 +24,6 @@ func TestFormatter(t *testing.T) {
 		description string
 		input       string
 		expect      string
-		panics      bool
 	}{
 		{
 			description: "very simple",
@@ -437,24 +434,7 @@ block2 {
 }
 `,
 		},
-		{
-			description: "very long heredoc from fuzzer",
-			input: func() string {
-				bs, _ := os.ReadFile("testdata/clusterfuzz-testcase-minimized-fuzz-format-5806400649363456")
-				return string(bs)
-			}(),
-			panics: true,
-		},
 	} {
-		t.Run(fmt.Sprintf("test case %d: %s", i, tc.description), func(t *testing.T) {
-			if tc.panics {
-				defer func() {
-					if r := recover(); r == nil {
-						t.Errorf("[TEST %d: %s] Expected panic, but got none", i, tc.description)
-					}
-				}()
-			}
-
 		// the formatter should output a trailing newline,
 		// even if the tests aren't written to expect that
 		if !strings.HasSuffix(tc.expect, "\n") {
@@ -463,10 +443,9 @@ block2 {
 
 		actual := Format([]byte(tc.input))
 
-			if !tc.panics && string(actual) != tc.expect {
+		if string(actual) != tc.expect {
 			t.Errorf("\n[TEST %d: %s]\n====== EXPECTED ======\n%s\n====== ACTUAL ======\n%s^^^^^^^^^^^^^^^^^^^^^",
 				i, tc.description, string(tc.expect), string(actual))
 		}
-		})
 	}
 }

caddyconfig/caddyfile/lexer.go

@@ -149,10 +149,6 @@ func (l *lexer) next() (bool, error) {
 				continue
 			}
 
-			if len(val) > 32 {
-				return false, fmt.Errorf("heredoc marker too long on line #%d: %s", l.line, string(val))
-			}
-
 			// after hitting a newline, we know that the heredoc marker
 			// is the characters after the two << and the newline.
 			// we reset the val because the heredoc is syntax we don't