ci: revisit/fix coverage uploading (#10201)

* Add ci/common/submit_coverage.sh, used with Travis and AppVeyor

* use gcovr, with coverage.xml for better branch coverage reporting, and
  easier processing of gcov files in general

* codecov: use flags again, with `uname -s` additionally
  Ref: https://github.com/neovim/neovim/pull/10227#issuecomment-502923543

* remove now unused parsers.gcov config from codecov.yml

4 files changed, 48 insertions, 14 deletions

diff --git a/ci/build.ps1 b/ci/build.ps1
index d3686e2914..c68b3fccb4 100644
--- a/ci/build.ps1
+++ b/ci/build.ps1
@@ -43,6 +43,7 @@ if ($compiler -eq 'MINGW') {
   if ($compileOption -eq 'gcov') {
     $nvimCmakeVars['USE_GCOV'] = 'ON'
     $uploadToCodecov = $true
+    $env:GCOV = "C:\msys64\mingw$bits\bin\gcov"
   }
   # These are native MinGW builds, but they use the toolchain inside
   # MSYS2, this allows using all the dependencies and tools available
@@ -119,13 +120,16 @@ cmake --build . --config $cmakeBuildType --target functionaltest -- $cmakeGenera
   foreach { $failed = $failed -or
     $_ -match 'functional tests failed with error'; $_ }
 if ($failed) {
+  if ($uploadToCodecov) {
+    bash -l /c/projects/neovim/ci/common/submit_coverage.sh functionaltest
+  }
   exit $LastExitCode
 }
 Set-PSDebug -Strict -Trace 1
 
 
 if ($uploadToCodecov) {
-  C:\msys64\usr\bin\bash -lc "cd /c/projects/neovim; bash <(curl -s https://codecov.io/bash) -c || echo 'codecov upload failed.'"
+  bash -l /c/projects/neovim/ci/common/submit_coverage.sh functionaltest
 }
 
 # Old tests
@@ -135,7 +139,7 @@ $env:PATH = "C:\msys64\usr\bin;$env:PATH"
 & "C:\msys64\mingw$bits\bin\mingw32-make.exe" -C $(Convert-Path ..\src\nvim\testdir) VERBOSE=1
 
 if ($uploadToCodecov) {
-  C:\msys64\usr\bin\bash -lc "cd /c/projects/neovim; bash <(curl -s https://codecov.io/bash) -c || echo 'codecov upload failed.'"
+  bash -l /c/projects/neovim/ci/common/submit_coverage.sh oldtest
 }
 
 # Build artifacts
diff --git a/ci/common/submit_coverage.sh b/ci/common/submit_coverage.sh
new file mode 100755
index 0000000000..7c343268d1
--- /dev/null
+++ b/ci/common/submit_coverage.sh
@@ -0,0 +1,41 @@
+#!/bin/sh
+# Collect and submit coverage reports.
+#
+# Args:
+# $1: Flag(s) for codecov, separated by comma.
+
+set -ex
+
+# Change to grandparent dir (POSIXly).
+CDPATH='' cd -P -- "$(dirname -- "$0")/../.." || exit
+
+echo "=== running submit_coverage in $PWD: $* ==="
+"$GCOV" --version
+
+# Download/install codecov-bash and gcovr once.
+codecov_sh="${TEMP:-/tmp}/codecov.bash"
+if ! [ -f "$codecov_sh" ]; then
+  curl --retry 5 --silent --fail -o "$codecov_sh" https://codecov.io/bash
+  chmod +x "$codecov_sh"
+
+  python3 -m pip install --quiet --user gcovr
+fi
+
+python3 -m gcovr --branches --exclude-unreachable-branches --print-summary -j 2 --exclude '.*/auto/.*' --root build --delete -o coverage.xml --xml
+
+# Upload to codecov.
+# -X gcov: disable gcov, done manually above.
+# -Z: exit non-zero on failure
+# -F: flag(s)
+# NOTE: ignoring flags for now, since this causes timeouts on codecov.io then,
+#       which they know about for about a year already...
+# Flags must match pattern ^[\w\,]+$ ("," as separator).
+codecov_flags="$(uname -s),${1}"
+codecov_flags=$(echo "$codecov_flags" | sed 's/[^,_a-zA-Z0-9]/_/g')
+if ! "$codecov_sh" -f coverage.xml -X gcov -Z -F "${codecov_flags}"; then
+  echo "codecov upload failed."
+fi
+
+# Cleanup always, especially collected data.
+find . \( -name '*.gcov' -o -name '*.gcda' \) -ls -delete | wc -l
+rm -f coverage.xml
diff --git a/ci/common/test.sh b/ci/common/test.sh
index 0912c3965f..e25af4d56c 100644
--- a/ci/common/test.sh
+++ b/ci/common/test.sh
@@ -3,10 +3,7 @@
 
 submit_coverage() {
   if [ -n "${GCOV}" ]; then
-    if curl --fail --output codecov.bash --silent https://codecov.io/bash; then
-      bash codecov.bash -c || echo "codecov upload failed."
-      rm -f codecov.bash
-    fi
+    "${CI_DIR}/common/submit_coverage.sh" "$@" || echo 'codecov upload failed.'
   fi
 }
 
diff --git a/codecov.yml b/codecov.yml
index 5acc64f756..a83fd916ee 100644
--- a/codecov.yml
+++ b/codecov.yml
@@ -24,12 +24,4 @@ coverage:
         only_pulls: true
     changes: no
 
-parsers:
-  gcov:
-    branch_detection:
-      conditional: yes
-      loop: yes
-      method: no
-      macro: no
-
 comment: off