add unit test and update readme

README.md

@@ -33,7 +33,7 @@ cargo add tailwind-fuse
 You can use [`tw_join!`] to join Tailwind classes, and [`tw_merge!`] to merge Tailwind Classes handling conflicts.
 
 
-You can use anything that implements [`AsRef<str>`] or [`AsTailwindClass`]
+You can use anything that implements [`AsTailwindClass`]
 
 ```rust
 use tailwind_fuse::*;
@@ -46,12 +46,30 @@ assert_eq!(
 
 // Conflict resolution
 // Right most class takes precedence
-assert_eq!("p-4", tw_merge!("py-2 px-4", "p-4"));
+assert_eq!(
+   "p-4",
+   tw_merge!("py-2 px-4", "p-4")
+);
 
 // Refinements are permitted
-assert_eq!("p-4 py-2", tw_merge!("p-4", "py-2"));
+assert_eq!(
+   "p-4 py-2",
+   tw_merge!("p-4", "py-2")
+);
+```
+
+You can use Options to exclude certain classes from being merged
+
+```rust
+use tailwind_fuse::*;
+
+assert_eq!(
+  "flex justify-center",
+  tw_join!("flex", (false).then_some("items-center"), (true).then_some("justify-center"))
+)
 ```
 
+
 ## Usage: Variants
 
 Useful for building components with first class support for tailwind. By default, conflicts are merged using [`tw_merge()`].

fuse/src/core/join.rs

@@ -106,7 +106,7 @@ macro_rules! tw_join {
 }
 
 #[test]
-fn test_tw() {
+fn join() {
     assert_eq!(tw_join!("a"), "a");
     assert_eq!(tw_join!("a", "b"), "a b");
     assert_eq!(tw_join!("a", "b", "c"), "a b c");
@@ -119,4 +119,9 @@ fn test_tw() {
         "one two three"
     );
     assert_eq!(tw_join!("a", "    ", "b", "c", " "), "a b c");
+
+    assert_eq!(
+        tw_join!("a", (false).then_some("b"), (true).then_some("c")),
+        "a c"
+    )
 }

fuse/src/lib.rs

@@ -33,7 +33,7 @@
 //! You can use [`tw_join!`] to join Tailwind classes, and [`tw_merge!`] to merge Tailwind Classes handling conflicts.
 //!
 //!
-//! You can use anything that implements [`AsRef<str>`] or [`AsTailwindClass`]
+//! You can use anything that implements [`AsTailwindClass`]
 //!
 //! ```
 //! use tailwind_fuse::*;
@@ -46,12 +46,30 @@
 //!
 //! // Conflict resolution
 //! // Right most class takes precedence
-//! assert_eq!("p-4", tw_merge!("py-2 px-4", "p-4"));
+//! assert_eq!(
+//!    "p-4",
+//!    tw_merge!("py-2 px-4", "p-4")
+//! );
 //!
 //! // Refinements are permitted
-//! assert_eq!("p-4 py-2", tw_merge!("p-4", "py-2"));
+//! assert_eq!(
+//!    "p-4 py-2",
+//!    tw_merge!("p-4", "py-2")
+//! );
+//! ```
+//!
+//! You can use Options to exclude certain classes from being merged
+//!
+//! ```
+//! use tailwind_fuse::*;
+//!
+//! assert_eq!(
+//!   "flex justify-center",
+//!   tw_join!("flex", (false).then_some("items-center"), (true).then_some("justify-center"))
+//! )
 //! ```
 //!
+//!
 //! ## Usage: Variants
 //!
 //! Useful for building components with first class support for tailwind. By default, conflicts are merged using [`tw_merge()`].