For example, if you try to match `*a*` against `ab`, then we check:
```
left = ""
middle = "a"
right = ""
middle in name[len(left):len(name)-len(right)]:
"a" in "ab"[len(""):len(name)-len("")]:
"a" in "ab"[0:-0]
"a" in "" => False
```
The problem here is that negative numbers in python index from the back, but -0 is not a negative number, so it always results in the empty string.
Previously, I was getting the error
`Expected external/_main~toolchains~toolchain_sdk/usr/bin/clang++ to start with one of ["external/_main~toolchains~toolchain_sdk//", "bazel-out/k8-dbg/bin/external/_main~toolchains~toolchain_sdk/"]`
Matt