fix: update rustcov to use source coverage

See https://doc.rust-lang.org/nightly/unstable-book/compiler-flags/instrument-coverage.html

Author: chaaz

rustcov

@@ -1,123 +1,51 @@
 # #!/usr/bin/env bash
 
-# (roughly) from https://github.com/mozilla/grcov , but don't use
-# codecov.io
+# From
 #
-# Writes a `target/coverage/report/index.html`, and outputs (at the end)
-# something like
+# https://doc.rust-lang.org/nightly/unstable-book/compiler-flags/instrument-coverage.html
 #
-# ```
-# Overall coverage rate:
-#   lines......: 100.0% (57 of 57 lines)
-#   functions..: 69.8% (30 of 43 functions)
-# ```
+# and
 #
-# functions% is useless: grcov does not understand rust functions, but
-# lines% should get to 100% if you want complete coverage. The trick is
-# to put network code, long loops, and other non-unit-testable code in
-# `*system*.rs` files, which have trival `#[cfg(test)]` implementations.
-# Make sure you justify in comments why they should be excluded from
-# coverage.
-#
-# If you don't have `/target` added to your `.gitignore`, `.ignore`,
-# etc. files for some reason, you should at least include
-# `/target/coverage`
-#
-# first (MacOS):
-# ```
-# rustup toolchain install nightly  # for -Zprofile
+# https://marco-c.github.io/2020/11/24/rust-source-based-code-coverage.html
+
+## Do this first:
+
 # rustup component add llvm-tools-preview
+# cargo install cargo-binutils
+# cargo profdata -- --help
 # cargo install grcov
-# brew install lcov  # for genhtml
-# ```
-
-set -e
 
-if [[ ! -f Cargo.toml ]] ; then
-  echo "ERROR: Must run in a root cargo project"
-  exit -1
-fi
+cmdname=`basename $0`
 
 usage() {
   exitcode="$1"
   cat << USAGE >&2
 Usage:
   $cmdname [options]
-  -d   Run dirty (don't clean): only use this if you
-       haven't run cargo at all since the last rustcov.
   -h   Show this message
 USAGE
   exit "$exitcode"
 }
 
-# Get our options
-dirty=0
-while getopts "dh" opt ; do
+while getopts "h" opt ; do
   case $opt in
-    d) dirty=1 ;;
     h) usage 0 ;;
   esac
 done
 
-# Assume that the name of the project is the same as `pwd`
-pname=$(basename `pwd`)
-uname=$(echo $pname | tr - _)
-tdir=target/coverage
-
-cargo_targets=$(
-  IFS=$'\n'
-  meta=`cargo +nightly metadata --format-version 1`
-  for m in `jq -r '.workspace_members[]' <<< "$meta"` ; do
-    jq -r ".packages[] | select(.id == \"$m\") | .targets[] | select(.kind[0] != \"custom-build\") | .name" <<< "$meta" | tr - _
-  done
-)
-cargo_targets=$(xargs echo <<< "$cargo_targets")
-
-workspace_members=$(
-  cargo +nightly metadata --format-version 1 | jq -r '.workspace_members[]' | cut -d' ' -f1
-)
-workspace_members=$(xargs echo <<< "$workspace_members")
-
-echo "running tests/coverage for ${cargo_targets}"
-
-export CARGO_INCREMENTAL=0
-export RUSTFLAGS="-Zprofile -Ccodegen-units=1 -Copt-level=0 -Clink-dead-code -Coverflow-checks=off -Zpanic_abort_tests -Cpanic=abort"
-export RUSTDOCFLAGS="-Cpanic=abort"
-
-# Inelegent, but effective. We use --target on the cargo command to
-# prevent build scripts from seeing RUSTFLAGS (this is a
-# perhaps-temporarily intention of cargo). Some build scripts like
-# etcd-rs end up using panic/unwind, which panic=abort will cause to
-# fail.
-target=$(rustup show | grep default | sed -e "s/^[^-]*-\(.*\) .*/\1/")
-
-# Painful, but we need a complete build to coverage check.
-if [ $dirty == "0" ] ; then
-  for w in "$workspace_members" ; do
-    cargo +nightly clean -p "$w" --target ${target}
-  done
-  find target -name '*.gc*' -delete
-else
-  find target -name '*.gcda' -delete
-fi
-rm -rf ${tdir}
+# echo cargo +nightly test "${@:$OPTIND}"
 
-# Actually (build and then) run tests
-cargo +nightly test --target ${target} "${@:$OPTIND}"
+cargo clean
 
-mkdir -p ${tdir}
+RUSTFLAGS="-Z instrument-coverage" \
+  LLVM_PROFILE_FILE="testing-%m.profraw" \
+  cargo +nightly test "${@:$OPTIND}"
 
-# zip -0 ${tdir}/ccov.zip `find . \( -name "${uname}*.gc*" \) -print`
-# grcov ${tdir}/ccov.zip -s . -t lcov --llvm --branch --ignore-not-existing \
-#       --ignore 'target/*' --ignore "/*" --ignore '*system*' \
-#       -o ${tdir}/lcov.info
+mkdir -p target/coverage
 
-grcov . -s . -t lcov --llvm --branch --ignore-not-existing \
-      --ignore 'target/*' --ignore "/*" --ignore '*system*' \
-      -o ${tdir}/lcov.info
+grcov . -b target/debug/deps \
+      -s . -t html --ignore 'target/*' --ignore '/*' \
+      --ignore-not-existing -o ./target/coverage
 
-genhtml -o ${tdir}/report/ --show-details --highlight --ignore-errors source \
-        --legend ${tdir}/lcov.info | tee ${tdir}/output
+rm -f testing-*.profraw
 
-# fail if there is no `100` in `lines...:` of genhtml output
-tail -5 ${tdir}/output | grep -i lines | grep -q 100