pkg/manager: match full function names in focus areas

When configuring focus areas before directed fuzzing, construct regular
expressions that match the exact function names. Otherwise, we end up
adding more functions than intended.

Author: a-nogikh

pkg/manager/diff.go

@@ -10,6 +10,7 @@ import (
 	"fmt"
 	"math/rand"
 	"net"
+	"regexp"
 	"sort"
 	"strings"
 	"sync"
@@ -817,11 +818,15 @@ func PatchFocusAreas(cfg *mgrconfig.Config, gitPatches [][]byte, baseHashes, pat
 	funcs := modifiedSymbols(baseHashes, patchedHashes)
 	if len(funcs) > 0 {
 		log.Logf(0, "adding modified_functions to focus areas: %q", funcs)
+		var regexps []string
+		for _, name := range funcs {
+			regexps = append(regexps, fmt.Sprintf("^%s$", regexp.QuoteMeta(name)))
+		}
 		cfg.Experimental.FocusAreas = append(cfg.Experimental.FocusAreas,
 			mgrconfig.FocusArea{
 				Name: symbolsArea,
 				Filter: mgrconfig.CovFilterCfg{
-					Functions: funcs,
+					Functions: regexps,
 				},
 				Weight: 6.0,
 			})

pkg/manager/diff_test.go

@@ -55,7 +55,7 @@ index 103167d..fbf7a68 100644
 		{
 			Name: symbolsArea,
 			Filter: mgrconfig.CovFilterCfg{
-				Functions: []string{"function"},
+				Functions: []string{"^function$"},
 			},
 			Weight: 6.0,
 		},