Bob Nystrom
5f16a3a1cc
The previous implementation of List.+ used conditional checks (`this.count > 0`, `that.count > 0`) before iterating, which caused the loop body to be skipped entirely for empty lists. This commit removes those guards, allowing the for-in loops to run unconditionally — the Wren VM's iterate/iterateValue protocol already handles the empty case correctly at the native level. Additionally, the `list_iterate` native in `wren_core.c` now returns `false` immediately when the list count is zero and the iterator argument is null, preventing an out-of-bounds index of 0 from being returned for empty lists. The test file `test/list/concat.wren` is renamed to `test/list/plus.wren` and extended with a check that the original list `a` remains unmodified after concatenation. A new test in `test/list/iterate.wren` verifies that iterating over an empty list returns `false`.
The Wren scripts in this directory get converted to C string literals and then inserted into their respective .c files so that the interpreter can load them directly without having to do any file IO.
The script that does this copying is script/generate_builtins.py.
You can invoke using make builtin.