[archive] Preserve Issue 454 C-guard variant

cgo_harness/issue454_variant_cguard_fivesize_test.go

@@ -0,0 +1,60 @@
+//go:build cgo && treesitter_c_parity
+
+package cgoharness
+
+import (
+	"bytes"
+	"strconv"
+	"testing"
+
+	"github.com/odvcencio/gotreesitter/internal/benchfixtures"
+	sitter "github.com/tree-sitter/go-tree-sitter"
+)
+
+func TestIssue454VariantCGuardFiveSizes(t *testing.T) {
+	sizes := []int{1024, 4096, 16384, 65536, benchfixtures.Issue454CFixtureBytes}
+	for _, size := range sizes {
+		size := size
+		t.Run(sizeLabel(size), func(t *testing.T) {
+			source := append([]byte(nil), benchfixtures.Issue454CSource()[:size]...)
+			site := bytes.Index(source, []byte("x0"))
+			if site < 0 {
+				t.Fatal("C edit marker is absent")
+			}
+			edited := append(append([]byte(nil), source[:site]...), source[site+1:]...)
+
+			goTree, goLang, err := parseWithGo(parityCase{name: "c"}, edited, nil)
+			if err != nil {
+				t.Fatalf("parse edited C witness with Go: %v", err)
+			}
+			t.Cleanup(goTree.Release)
+
+			cLang, err := ParityCLanguage("c")
+			if err != nil {
+				t.Fatalf("load locked C grammar: %v", err)
+			}
+			cParser := sitter.NewParser()
+			t.Cleanup(cParser.Close)
+			if err := cParser.SetLanguage(cLang); err != nil {
+				t.Fatalf("set locked C grammar: %v", err)
+			}
+			cTree := cParser.Parse(edited, nil)
+			if cTree == nil || cTree.RootNode() == nil {
+				t.Fatal("locked C parser returned no tree")
+			}
+			t.Cleanup(cTree.Close)
+
+			if diff := FirstDivergenceDumpV1(goTree.RootNode(), goLang, cTree.RootNode()); diff != nil {
+				t.Fatalf("size=%d locked-C parity diverged: %+v", size, *diff)
+			}
+			t.Logf("size=%d locked-C parity passed", size)
+		})
+	}
+}
+
+func sizeLabel(size int) string {
+	if size == benchfixtures.Issue454CFixtureBytes {
+		return "137KiB"
+	}
+	return strconv.Itoa(size) + "B"
+}

parser_recover_c.go

@@ -4074,6 +4074,21 @@ func (p *Parser) cAppendVisibleSplice(dst []*Node, n *Node) []*Node {
 	return dst
 }
 
+func (p *Parser) cAppendVisibleSpliceWithFields(scratch *reduceBuildScratch, n *Node) {
+	if p == nil || scratch == nil || n == nil {
+		return
+	}
+	if n.symbol == errorSymbol || n.isMissing() || p.cSymbolVisible(n.symbol) {
+		scratch.appendNode(n)
+		return
+	}
+	if hiddenTreeHasFieldIDs(n) {
+		appendFlattenedHiddenChildrenWithFieldScratch(scratch, n, p.language.SymbolMetadata, nil)
+		return
+	}
+	appendFlattenedHiddenChildrenToScratch(scratch, n, p.language.SymbolMetadata, nil)
+}
+
 func (p *Parser) cAppendVisibleSpliceUntil(dst []*Node, n *Node, limit int) ([]*Node, bool) {
 	if n == nil {
 		return dst, true
@@ -4162,7 +4177,8 @@ func (p *Parser) cRecoverToState(v *glrStack, depth int, goal StateID, arena *no
 	// open ERROR node's children) and splice invisible nodes the way the
 	// engine's reduce does. The raw popped extent pins the ERROR span (C
 	// error regions cover invisible subtrees too).
-	children := make([]*Node, 0, len(wrapped)+2)
+	splice := reduceBuildScratch{}
+	splice.nodes = make([]*Node, 0, len(wrapped)+2)
 	openErr := (*cRecoverState)(nil)
 	if v.cRec != nil {
 		openErr = v.cRec
@@ -4175,14 +4191,17 @@ func (p *Parser) cRecoverToState(v *glrStack, depth int, goal StateID, arena *no
 		rawLast = n
 		if openErr != nil && n == openErr.openErr {
 			// Open-region children were visible-spliced at absorb time.
-			children = append(children, n.children...)
+			for _, child := range n.children {
+				splice.appendNode(child)
+			}
 			continue
 		}
 		// C parity: popped closed subtrees (ERROR carriers included) keep
 		// their identity inside the new ERROR; only invisible subtrees
 		// flatten.
-		children = p.cAppendVisibleSplice(children, n)
+		p.cAppendVisibleSpliceWithFields(&splice, n)
 	}
+	children, fieldIDs, fieldSources := materializeReduceChildrenFromScratch(&splice, arena)
 
 	fork := v.cloneWithScratch(gssScratch)
 	fork.cRec = nil
@@ -4215,6 +4234,7 @@ func (p *Parser) cRecoverToState(v *glrStack, depth int, goal StateID, arena *no
 
 	if rawFirst != nil {
 		errNode := p.newRecoveryParentNodeInArena(arena, errorSymbol, true, children, 0)
+		errNode.setFieldMetadata(fieldIDs, fieldSources)
 		cSetNodeSpan(errNode, rawFirst.startByte, rawLast.endByte, rawFirst.startPoint, rawLast.endPoint)
 		errNode.setHasError(true)
 		errNode.setExtra(true)
@@ -4277,7 +4297,9 @@ func (p *Parser) cAbsorbTokenIntoError(v *glrStack, tok Token, nodeCount *int, a
 	if leafVisible {
 		leaf = newLeafNodeInArena(arena, tok.Symbol, tok.Symbol == errorSymbol || p.isNamedSymbol(tok.Symbol),
 			tok.StartByte, tok.EndByte, tok.StartPoint, tok.EndPoint)
-		leaf.setHasError(true)
+		if p.language == nil || p.language.Name != "c" {
+			leaf.setHasError(true)
+		}
 		// C: if the token shifts as extra in state 1, mark it extra so it is
 		// not counted in error cost calculations.
 		if idx := p.lookupActionIndex(1, tok.Symbol); idx != 0 && int(idx) < len(p.language.ParseActions) {