fix(fuzz): reduce mem budget to prevent timeouts (#913)

thevilledev · web-flow · commit 553025ac7d0b · 2026-01-24T11:25:47.000+01:00
Fixes OSS-Fuzz timeout caused by expressions like "-817810..178"
creating ~818K element arrays that exceeded the 60s timeout when
passed to fmt.Sprintf for string formatting.

Signed-off-by: Ville Vesilehto &lt;ville@vesilehto.fi&gt;
diff --git a/test/fuzz/fuzz_test.go b/test/fuzz/fuzz_test.go
@@ -7,6 +7,7 @@ import (
 	"testing"
 
 	"github.com/expr-lang/expr"
+	"github.com/expr-lang/expr/vm"
 )
 
 //go:embed fuzz_corpus.txt
@@ -76,7 +77,8 @@ func FuzzExpr(f *testing.F) {
 			t.Skipf("compile error: %s", err)
 		}
 
-		_, err = expr.Run(program, env)
+		v := vm.VM{MemoryBudget: 500000}
+		_, err = v.Run(program, env)
 		if err != nil {
 			for _, r := range skip {
 				if r.MatchString(err.Error()) {

Original file line number	Diff line number	Diff line change
`@@ -7,6 +7,7 @@ import (`
`7`	`7`	`"testing"`
`8`	`8`
`9`	`9`	`"github.com/expr-lang/expr"`
	`10`	`+ "github.com/expr-lang/expr/vm"`
`10`	`11`	`)`
`11`	`12`
`12`	`13`	`//go:embed fuzz_corpus.txt`
`@@ -76,7 +77,8 @@ func FuzzExpr(f *testing.F) {`
`76`	`77`	`t.Skipf("compile error: %s", err)`
`77`	`78`	`}`
`78`	`79`
`79`		`- _, err = expr.Run(program, env)`
	`80`	`+ v := vm.VM{MemoryBudget: 500000}`
	`81`	`+ _, err = v.Run(program, env)`
`80`	`82`	`if err != nil {`
`81`	`83`	`for _, r := range skip {`
`82`	`84`	`if r.MatchString(err.Error()) {`