new env var: USE_SYSTEM_NIM

README.md

@@ -4,6 +4,12 @@
 
 GNU Make, Bash and the usual POSIX utilities.
 
+## Make flags
+
+* use the system Nim instead of the shipped version (usually for testing Nim devel versions)
+
+`make USE_SYSTEM_NIM=1 test`
+
 ## License
 
 Licensed and distributed under either of

makefiles/variables.mk

@@ -82,3 +82,6 @@ endif
 # AppVeyor/Travis cache of $(NIM_DIR)/bin
 CI_CACHE :=
 
+# bypassing the shipped Nim, usually for testing new Nim devel versions
+USE_SYSTEM_NIM := 0
+

scripts/env.sh

@@ -26,9 +26,14 @@ export NIM_PATH=$(cd "${ABS_PATH}/../vendor/Nim/bin"; pwd)
 # Nimble needs this to be an absolute path
 export NIMBLE_DIR=$(cd "${ABS_PATH}/../../.nimble"; pwd)
 
+# we don't use Nimble-installed binaries, but just in case
+export PATH="${NIMBLE_DIR}/bin:${PATH}"
+
 #- make it an absolute path, so we can call this script from other dirs
 #- we can't use native Windows paths in here, because colons can't be escaped in PATH
-export PATH="${NIM_PATH}:${NIMBLE_DIR}/bin:${PATH}"
+if [[ "$USE_SYSTEM_NIM" != "1" ]]; then
+	export PATH="${NIM_PATH}:${PATH}"
+fi
 
 # used by nim-beacon-chain/tests/simulation/start.sh
 export BUILD_OUTPUTS_DIR="${ABS_PATH}/../../../build"