zig fmt: properly revert nested asm indentation

lib/std/zig/Ast/Render.zig

@@ -2775,6 +2775,8 @@ fn renderAsm(
     ais.forceLastIndent(); // Might have been dedented by a multiline string literal
     assert(ais.current_line_empty);
 
+    const prev_indent_delta = ais.indent_delta; // May be part of another asm expression
+    // so indent_delta can't be unconditionally used
     ais.setIndentDelta(asm_indent_delta);
     const colon1 = tree.lastToken(asm_node.ast.template) + 1;
 
@@ -2856,7 +2858,7 @@ fn renderAsm(
     const clobbers = asm_node.ast.clobbers.unwrap().?;
     try renderExpression(r, clobbers, .none);
     ais.forceLastIndent(); // Might have been dedented by a multiline string literal
-    ais.setIndentDelta(indent_delta);
+    ais.setIndentDelta(prev_indent_delta);
     ais.popIndent();
     return renderToken(r, asm_node.ast.rparen, space); // rparen
 }

lib/std/zig/parser_test.zig

@@ -6859,6 +6859,18 @@ test "zig fmt: array init of labeled block" {
     );
 }
 
+test "zig fmt: nested asm indentation" {
+    try testCanonical(
+        \\const A = asm (""
+        \\    : [_] "" (_),
+        \\    :
+        \\    : asm (""
+        \\      : [_] "" (_),
+        \\    ));
+        \\
+    );
+}
+
 test "recovery: top level" {
     try testError(
         \\test "" {inline}