Add bad template width test

src/lib.rs

@@ -153,8 +153,6 @@ use crate::r#type::{Type, Precision};
 
 // TODO:
 // * Put compile checks behind different target so compiler updates don't break building.
-// * Incorrect template size test.
-// * Move macro bases to their own files.
 // After 0.1.0:
 // * Create abstract syntax trees instead of quoting prematurely.
 // ** Add comments that show example macro expansion fragments.

tests/compile_failures/splitbits_bad_template_width.rs

@@ -0,0 +1,6 @@
+use splitbits::splitbits;
+
+fn main() {
+    let input = 5;
+    splitbits!(input, "aaaabbb");
+}

tests/compile_failures/splitbits_bad_template_width.stderr

@@ -0,0 +1,7 @@
+error: proc macro panicked
+ --> tests/compile_failures/splitbits_bad_template_width.rs:5:5
+  |
+5 |     splitbits!(input, "aaaabbb");
+  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  |
+  = help: message: Template must have a valid width: "Template width must be 8, 16, 32, 64, or 128, but was 7."