From 1673022fa6c100afe6309e55259addf6e19aa8d0 Mon Sep 17 00:00:00 2001
From: pfg <pfg@pfg.pw>
Date: Wed, 28 Aug 2024 00:47:36 -0700
Subject: [PATCH 1/2] Support stringifying non-exhaustive enum to json

---
 lib/std/json/stringify.zig      | 17 ++++++++++++++++-
 lib/std/json/stringify_test.zig |  9 +++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/lib/std/json/stringify.zig b/lib/std/json/stringify.zig
index 965b7c3113c9..2fdfc671452f 100644
--- a/lib/std/json/stringify.zig
+++ b/lib/std/json/stringify.zig
@@ -540,11 +540,26 @@ pub fn WriteStream(
                         return try self.write(null);
                     }
                 },
-                .Enum, .EnumLiteral => {
+                .Enum => |enum_info| {
                     if (std.meta.hasFn(T, "jsonStringify")) {
                         return value.jsonStringify(self);
                     }
 
+                    if (!enum_info.is_exhaustive) {
+                        inline for (enum_info.fields) |field| {
+                            if (value == @field(T, field.name)) {
+                                break;
+                            }
+                        } else {
+                            try self.valueStart();
+                            try self.stream.print("{d}", .{@intFromEnum(value)});
+                            return self.valueDone();
+                        }
+                    }
+
+                    return self.stringValue(@tagName(value));
+                },
+                .EnumLiteral => {
                     return self.stringValue(@tagName(value));
                 },
                 .Union => {
diff --git a/lib/std/json/stringify_test.zig b/lib/std/json/stringify_test.zig
index c0003b87dcc5..52e38d1e30ad 100644
--- a/lib/std/json/stringify_test.zig
+++ b/lib/std/json/stringify_test.zig
@@ -172,6 +172,15 @@ test "stringify enums" {
     try testStringify("\"bar\"", E.bar, .{});
 }
 
+test "stringify non-exhaustive enum" {
+    const E = enum(u8) {
+        foo = 0,
+        _,
+    };
+    try testStringify("\"foo\"", E.foo, .{});
+    try testStringify("1", @as(E, @enumFromInt(1)), .{});
+}
+
 test "stringify enum literals" {
     try testStringify("\"foo\"", .foo, .{});
     try testStringify("\"bar\"", .bar, .{});

From c64ca0a7d0672f1e10539baef93e42b9316a5451 Mon Sep 17 00:00:00 2001
From: pfg <pfg@pfg.pw>
Date: Sat, 7 Sep 2024 00:19:22 -0400
Subject: [PATCH 2/2] Add documentation and use a recursive call rather than
 calling write directly

---
 lib/std/json/stringify.zig | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/std/json/stringify.zig b/lib/std/json/stringify.zig
index 2fdfc671452f..d568f01c6ef6 100644
--- a/lib/std/json/stringify.zig
+++ b/lib/std/json/stringify.zig
@@ -483,6 +483,7 @@ pub fn WriteStream(
         ///      * If the union declares a method `pub fn jsonStringify(self: *@This(), jw: anytype) !void`, it is called to do the serialization instead of the default behavior. The given `jw` is a pointer to this `WriteStream`.
         ///  * Zig `enum` -> JSON string naming the active tag.
         ///      * If the enum declares a method `pub fn jsonStringify(self: *@This(), jw: anytype) !void`, it is called to do the serialization instead of the default behavior. The given `jw` is a pointer to this `WriteStream`.
+        ///      * If the enum is non-exhaustive, unnamed values are rendered as integers.
         ///  * Zig untyped enum literal -> JSON string naming the active tag.
         ///  * Zig error -> JSON string naming the error.
         ///  * Zig `*T` -> the rendering of `T`. Note there is no guard against circular-reference infinite recursion.
@@ -551,9 +552,7 @@ pub fn WriteStream(
                                 break;
                             }
                         } else {
-                            try self.valueStart();
-                            try self.stream.print("{d}", .{@intFromEnum(value)});
-                            return self.valueDone();
+                            return self.write(@intFromEnum(value));
                         }
                     }