Revert "prog: auto-set proper conditional fields in Deserialize()"

This reverts commit 8e75c913b6f9b09cab2ad31fd7d66ea0d1703de8.

7 files changed, 15 insertions, 41 deletions

diff --git a/prog/encoding.go b/prog/encoding.go
index e925e7918..b5d5114ca 100644
--- a/prog/encoding.go
+++ b/prog/encoding.go
@@ -257,13 +257,9 @@ func (target *Target) Deserialize(data []byte, mode DeserializeMode) (*Prog, err
 	// This validation is done even in non-debug mode because deserialization
 	// procedure does not catch all bugs (e.g. mismatched types).
 	// And we can receive bad programs from corpus and hub.
-	if err := prog.validateWithOpts(validationOptions{
-		// Don't validate auto-set conditional fields. We'll patch them later.
-		ignoreTransient: true,
-	}); err != nil {
+	if err := prog.validate(); err != nil {
 		return nil, err
 	}
-	p.fixupConditionals(prog)
 	if p.autos != nil {
 		p.fixupAutos(prog)
 	}
@@ -1158,13 +1154,6 @@ func (p *parser) fixupAutos(prog *Prog) {
 	}
 }
 
-func (p *parser) fixupConditionals(prog *Prog) {
-	for _, c := range prog.Calls {
-		// Only overwrite transient union fields.
-		c.setDefaultConditions(p.target, true)
-	}
-}
-
 func (p *parser) Scan() bool {
 	if p.e != nil || len(p.data) == 0 {
 		return false
diff --git a/prog/expr.go b/prog/expr.go
index 38358b214..5ecbef8eb 100644
--- a/prog/expr.go
+++ b/prog/expr.go
@@ -174,7 +174,7 @@ func matchingUnionArgs(typ *UnionType, finder ArgFinder) []int {
 
 func (p *Prog) checkConditions() error {
 	for _, c := range p.Calls {
-		err := c.checkConditions(p.Target, false)
+		err := c.checkConditions(p.Target)
 		if err != nil {
 			return err
 		}
@@ -184,15 +184,12 @@ func (p *Prog) checkConditions() error {
 
 var ErrViolatedConditions = errors.New("conditional fields rules violation")
 
-func (c *Call) checkConditions(target *Target, ignoreTransient bool) error {
+func (c *Call) checkConditions(target *Target) error {
 	var ret error
 
 	makeArgFinder := argFinderConstructor(target, c)
 	forEachStaleUnion(target, c, makeArgFinder,
 		func(a *UnionArg, t *UnionType, okIndices []int) {
-			if ignoreTransient && a.transient {
-				return
-			}
 			ret = fmt.Errorf("%w union %s field is #%d(%s), but %v satisfy conditions",
 				ErrViolatedConditions, t.Name(), a.Index, t.Fields[a.Index].Name,
 				okIndices)
@@ -200,7 +197,7 @@ func (c *Call) checkConditions(target *Target, ignoreTransient bool) error {
 	return ret
 }
 
-func (c *Call) setDefaultConditions(target *Target, transientOnly bool) bool {
+func (c *Call) setDefaultConditions(target *Target) bool {
 	var anyReplaced bool
 	// Replace stale conditions with the default values of their correct types.
 	for {
@@ -208,9 +205,6 @@ func (c *Call) setDefaultConditions(target *Target, transientOnly bool) bool {
 		makeArgFinder := argFinderConstructor(target, c)
 		forEachStaleUnion(target, c, makeArgFinder,
 			func(unionArg *UnionArg, unionType *UnionType, okIndices []int) {
-				if transientOnly && !unionArg.transient {
-					return
-				}
 				// If several union options match, take the first one.
 				idx := okIndices[0]
 				field := unionType.Fields[idx]
diff --git a/prog/minimization.go b/prog/minimization.go
index 1760d180f..a9864aca2 100644
--- a/prog/minimization.go
+++ b/prog/minimization.go
@@ -281,7 +281,7 @@ func minimizeInt(ctx *minimizeArgsCtx, arg Arg, path string) bool {
 
 	// By mutating an integer, we risk violating conditional fields.
 	// If the fields are patched, the minimization process must be restarted.
-	patched := ctx.call.setDefaultConditions(ctx.p.Target, false)
+	patched := ctx.call.setDefaultConditions(ctx.p.Target)
 	if ctx.pred(ctx.p, ctx.callIndex0) {
 		*ctx.p0 = ctx.p
 		ctx.triedPaths[path] = true
diff --git a/prog/rand.go b/prog/rand.go
index 742dbaa7c..aca3163bd 100644
--- a/prog/rand.go
+++ b/prog/rand.go
@@ -886,7 +886,7 @@ func (a *UnionType) generate(r *randGen, s *state, dir Dir) (arg Arg, calls []*C
 	if a.isConditional() {
 		// Conditions may reference other fields that may not have already
 		// been generated. We'll fill them in later.
-		return a.DefaultArg(dir), nil
+		return a.DefaultTransientArg(dir), nil
 	}
 	index := r.Intn(len(a.Fields))
 	optType, optDir := a.Fields[index].Type, a.Fields[index].Dir(dir)
diff --git a/prog/test/fuzz_test.go b/prog/test/fuzz_test.go
index 2d063c469..f01905ea3 100644
--- a/prog/test/fuzz_test.go
+++ b/prog/test/fuzz_test.go
@@ -30,9 +30,6 @@ test$res2()
 test$res2()
 test$res2()
 `,
-		`r=test$res0()
-test$recur2(&(293324893027559)={r})
-`,
 	} {
 		t.Logf("test #%v: %q", i, data)
 		inp := []byte(data)[:len(data):len(data)]
diff --git a/prog/types.go b/prog/types.go
index 4e9d8455e..00440163b 100644
--- a/prog/types.go
+++ b/prog/types.go
@@ -735,9 +735,13 @@ func (t *UnionType) String() string {
 func (t *UnionType) DefaultArg(dir Dir) Arg {
 	idx := t.defaultField()
 	f := t.Fields[idx]
-	arg := MakeUnionArg(t, dir, f.DefaultArg(f.Dir(dir)), idx)
-	arg.transient = t.isConditional()
-	return arg
+	return MakeUnionArg(t, dir, f.DefaultArg(f.Dir(dir)), idx)
+}
+
+func (t *UnionType) DefaultTransientArg(dir Dir) Arg {
+	unionArg := t.DefaultArg(dir).(*UnionArg)
+	unionArg.transient = true
+	return unionArg
 }
 
 func (t *UnionType) defaultField() int {
diff --git a/prog/validation.go b/prog/validation.go
index f38dcd1e8..13b7c33db 100644
--- a/prog/validation.go
+++ b/prog/validation.go
@@ -21,25 +21,15 @@ func (p *Prog) debugValidate() {
 	}
 }
 
-func (p *Prog) validate() error {
-	return p.validateWithOpts(validationOptions{})
-}
-
 type validCtx struct {
 	target *Target
-	opts   validationOptions
 	args   map[Arg]bool
 	uses   map[Arg]Arg
 }
 
-type validationOptions struct {
-	ignoreTransient bool
-}
-
-func (p *Prog) validateWithOpts(opts validationOptions) error {
+func (p *Prog) validate() error {
 	ctx := &validCtx{
 		target: p.Target,
-		opts:   opts,
 		args:   make(map[Arg]bool),
 		uses:   make(map[Arg]Arg),
 	}
@@ -75,7 +65,7 @@ func (ctx *validCtx) validateCall(c *Call) error {
 			return err
 		}
 	}
-	if err := c.checkConditions(ctx.target, ctx.opts.ignoreTransient); err != nil {
+	if err := c.checkConditions(ctx.target); err != nil {
 		return err
 	}
 	return ctx.validateRet(c)