Script to gather test coverage for nushell (#234)

* Script to gather test coverage for nushell

Uses https://github.com/taiki-e/cargo-llvm-cov

Adapted to gather integration test from https://github.com/taiki-e/cargo-llvm-cov#get-coverage-of-external-tests

* Trim variable names

Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>

Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>

make_release/get_coverage.nu

@@ -0,0 +1,32 @@
+# Test coverage gathering for nushell 
+# Uses cargo-llvm-cov
+# Uses separate execution to track the integration tests
+# Hacked together by @sholderbach
+
+# Get test coverage for nushell
+def main [
+       --extra # Get coverage for extra features
+   ] {
+   cargo llvm-cov show-env --export-prefix | 
+       lines | 
+       str substring '7,' | 
+       split column '=' | 
+       str trim -c '"'  | 
+       transpose | 
+       headers | 
+       reject 'column1' | 
+       get 0 | 
+       str trim |
+       load-env
+   
+   cargo llvm-cov clean --workspace 
+   if $extra {
+       cargo build --workspace --features extra
+       cargo test --workspace --features extra
+   } else {
+       cargo build --workspace
+       cargo test --workspace
+   }
+   cargo llvm-cov --no-run --lcov --output-path lcov.info 
+   cargo llvm-cov --no-run --html
+}