Go: extract type parameters in type definitions

Signed-off-by: Masatake YAMATO <yamato@redhat.com>

Author: masatake

Units/parser-go.r/go-generics.d/expected.tags

@@ -13,3 +13,9 @@ F0	input.go	/^func F0[L ~[]M, M comparable, _, G any](s L, v M) int {$/;"	f	pack
 N	input.go	/^func F1[N ~[]O, O comparable, _ any](s N, v O) int {$/;"	Z	func:x.F1	typeref:constraint:~[]O	nth:0
 O	input.go	/^func F1[N ~[]O, O comparable, _ any](s N, v O) int {$/;"	Z	func:x.F1	typeref:constraint:comparable	nth:1
 F1	input.go	/^func F1[N ~[]O, O comparable, _ any](s N, v O) int {$/;"	f	package:x	typeref:typename:int	signature:(s N, v O)	tparams:[N ~[]O, O comparable, _ any]
+T	input.go	/^type List[T any] struct {$/;"	Z	struct:x.List	typeref:constraint:any	nth:0
+List	input.go	/^type List[T any] struct {$/;"	s	package:x	tparams:[T any]
+next	input.go	/^	next  *List[T]$/;"	m	struct:x.List	typeref:typename:*List
+value	input.go	/^	value T$/;"	m	struct:x.List	typeref:typename:T
+UUIDBuflen	input.go	/^	UUIDBuflen = 256$/;"	c	package:x
+UUID	input.go	/^type UUID [UUIDBuflen]byte$/;"	t	package:x	typeref:typename:[UUIDBuflen]byte

Units/parser-go.r/go-generics.d/input.go

@@ -30,3 +30,15 @@ func F0[L ~[]M, M comparable, _, G any](s L, v M) int {
 func F1[N ~[]O, O comparable, _ any](s N, v O) int {
     return -1
 }
+
+// Taken from https://go.dev/ref/spec#Type_definitions
+type List[T any] struct {
+	next  *List[T]
+	value T
+}
+
+// Taken from podman/vendor/github.com/digitalocean/go-libvirt/remote_protocol.gen.go
+const (
+	UUIDBuflen = 256
+)
+type UUID [UUIDBuflen]byte

parsers/go.c

@@ -842,6 +842,44 @@ static void attachConstraint (intArray *tparams_indexes, collector *constraint)
 	}
 }
 
+static bool isArraySpec (intArray *corks, vString *tparams_str)
+{
+	const char *cstr = vStringValue (tparams_str);
+	size_t cstr_len = vStringLength (tparams_str);
+
+	if (intArrayCount (corks) > 1 ||
+		(cstr_len > 2
+		 && cstr
+		 && cstr [cstr_len - 1] == ']'
+		 && cstr [cstr_len - 2] == ','))
+		return false;
+
+	for (unsigned int i = 0; i < intArrayCount (corks); i++)
+	{
+		int cork = intArrayItem (corks, i);
+		tagEntryInfo *e = getEntryInCorkQueue (cork);
+		if (!e)
+			return false;		/* Maybe "_" in the array. */
+
+		if (e->extensionFields.typeRef [0])
+			return false;		/* a constraint is given */
+	}
+
+	return true;
+}
+
+static void markCorkEntryAsPlaceholderInBatch (intArray *corks)
+{
+	for (unsigned int i = 0; i < intArrayCount (corks); i++)
+	{
+		int cork = intArrayItem (corks, i);
+		if (cork == CORK_NIL)
+			continue;
+
+		markCorkEntryAsPlaceholder (cork, true);
+	}
+}
+
 static intArray * parseTypeParameters (tokenInfo *const token, collector *tparams)
 {
 	// TypeParameters = "[" TypeParamList [ "," ] "]" .
@@ -908,6 +946,14 @@ static intArray * parseTypeParameters (tokenInfo *const token, collector *tparam
 	/* Read the next token as the other parser* functions do.
 	 * However, don't put the token to the collector. */
 	readToken (token);
+
+	if (isArraySpec (tparams_indexes, tparams->str))
+	{
+		markCorkEntryAsPlaceholderInBatch (tparams_indexes);
+		intArrayDelete (tparams_indexes);
+		tparams_indexes = NULL;
+	}
+
 	return tparams_indexes;
 }
 
@@ -1310,7 +1356,9 @@ static void parseConstTypeVar (tokenInfo *const token, goKind kind, const int sc
 	// IdentifierList = identifier { "," identifier } .
 	// ExpressionList = Expression { "," Expression } .
 	// TypeDecl     = "type" ( TypeSpec | "(" { TypeSpec ";" } ")" ) .
-	// TypeSpec     = identifier [ "=" ] Type .
+	// TypeSpec     = AliasDecl | TypeDef .
+	// AliasDecl    = identifier [ TypeParameters ] "=" Type .
+	// TypeDef      = identifier [ TypeParameters ] Type .
 	// VarDecl     = "var" ( VarSpec | "(" { VarSpec ";" } ")" ) .
 	// VarSpec     = IdentifierList ( Type [ "=" ExpressionList ] | "=" ExpressionList ) .
 	bool usesParens = false;
@@ -1330,15 +1378,30 @@ static void parseConstTypeVar (tokenInfo *const token, goKind kind, const int sc
 		tokenInfo *typeToken = NULL;
 		int member_scope = scope;
 
+		char *array_spec = NULL;
+
 		while (!isType (token, TOKEN_EOF))
 		{
 			if (isType (token, TOKEN_IDENTIFIER))
 			{
 				if (kind == GOTAG_TYPE)
 				{
+					vString *buffer = vStringNew ();
+					collector collector = COLLECTOR (buffer);
+					char *tparams = NULL;
+					intArray *tparams_indexes = NULL;
+
 					typeToken = newToken ();
 					copyToken (typeToken, token);
-					readToken (token);
+					readTokenFull (token, &collector);
+					if (isType (token, TOKEN_OPEN_SQUARE))
+					{
+						tparams_indexes = parseTypeParameters (token, &collector);
+						collectorTruncate (&collector, false);
+						tparams = vStringStrdup (buffer);
+					}
+					vStringDelete (buffer);
+
 					if (isType (token, TOKEN_EQUAL))
 					{
 						kind = GOTAG_TALIAS;
@@ -1356,7 +1419,29 @@ static void parseConstTypeVar (tokenInfo *const token, goKind kind, const int sc
 												scope, NULL, NULL);
 
 					if (member_scope != CORK_NIL)
+					{
+						tagEntryInfo *e = getEntryInCorkQueue (member_scope);
+						if (e && tparams_indexes)
+						{
+							fillScopeAndNthFields (member_scope, tparams_indexes);
+							if (tparams)
+								attachParserField (e, GoFields [F_TPARAMS].ftype, tparams);
+						}
+
 						registerEntry (member_scope);
+					}
+
+					if (tparams_indexes)
+					{
+						intArrayDelete (tparams_indexes); /* NULL is acceptable. */
+						tparams_indexes = NULL;
+						if (tparams)
+							eFree (tparams);
+					}
+					else
+						array_spec = tparams;
+					tparams = NULL;
+
 					break;
 				}
 				else
@@ -1381,7 +1466,7 @@ static void parseConstTypeVar (tokenInfo *const token, goKind kind, const int sc
 			else
 			{
 				/* Filling "typeref:" field of typeToken. */
-				vString *buffer = vStringNew ();
+				vString *buffer = vStringNewInit (array_spec ? array_spec : "");
 				collector collector = COLLECTOR(buffer);
 
 				collectorAppendToken (&collector, token);
@@ -1400,6 +1485,12 @@ static void parseConstTypeVar (tokenInfo *const token, goKind kind, const int sc
 				else
 					vStringDelete (buffer);
 			}
+
+			if (array_spec)
+			{
+				eFree (array_spec);
+				array_spec = NULL;
+			}
 			deleteToken (typeToken);
 		}
 		else if (corks)