refactor: move string-like structs into string module (#17369)

src/string/HashedString.zig

@@ -0,0 +1,43 @@
+const HashedString = @This();
+const bun = @import("root").bun;
+
+ptr: [*]const u8,
+len: u32,
+hash: u32,
+
+pub const empty = HashedString{ .ptr = @as([*]const u8, @ptrFromInt(0xDEADBEEF)), .len = 0, .hash = 0 };
+
+pub fn init(buf: []const u8) HashedString {
+    return HashedString{
+        .ptr = buf.ptr,
+        .len = @as(u32, @truncate(buf.len)),
+        .hash = @as(u32, @truncate(bun.hash(buf))),
+    };
+}
+
+pub fn initNoHash(buf: []const u8) HashedString {
+    return HashedString{
+        .ptr = buf.ptr,
+        .len = @as(u32, @truncate(buf.len)),
+        .hash = 0,
+    };
+}
+
+pub fn eql(this: HashedString, other: anytype) bool {
+    return Eql(this, @TypeOf(other), other);
+}
+
+fn Eql(this: HashedString, comptime Other: type, other: Other) bool {
+    switch (comptime Other) {
+        HashedString, *HashedString, *const HashedString => {
+            return ((@max(this.hash, other.hash) > 0 and this.hash == other.hash) or (this.ptr == other.ptr)) and this.len == other.len;
+        },
+        else => {
+            return @as(usize, this.len) == other.len and @as(u32, @truncate(bun.hash(other[0..other.len]))) == this.hash;
+        },
+    }
+}
+
+pub fn str(this: HashedString) []const u8 {
+    return this.ptr[0..this.len];
+}