directly print warnings from codeCheck

Makefile

@@ -64,12 +64,12 @@ restore-renv:    ## Restore renv to the state described in interactively
 
 check:           ## Check if the GAMS code follows the coding etiquette
                  ## using gms::codeCheck
-	Rscript -e 'invisible(gms::codeCheck(strict = TRUE))'
+	Rscript -e 'options(warn = 1); invisible(gms::codeCheck(strict = TRUE));'
 
 check-fix:       ## Check if the GAMS code follows the coding etiquette
                  ## and offer fixing any problems directly if possible
                  ## using gms::codeCheck
-	Rscript -e 'invisible(gms::codeCheck(strict = TRUE, interactive = TRUE))'
+	Rscript -e 'options(warn = 1); invisible(gms::codeCheck(strict = TRUE, interactive = TRUE));'
 
 test:            ## Test if the model compiles and runs without running a full
                  ## scenario. Tests take about 15 minutes to run.
@@ -79,7 +79,7 @@ test:            ## Test if the model compiles and runs without running a full
 test-fix:        ## First run codeCheck interactively, then test if the model compiles and runs without
                  ## running a full scenario. Tests take about 15 minutes to run.
 	$(info Tests take about 18 minutes to run, please be patient)
-	@Rscript -e 'invisible(gms::codeCheck(strict = TRUE, interactive = TRUE)); testthat::test_dir("tests/testthat"); message("Do not forget to commit changes done by codeCheck to not_used.txt files");'
+	@Rscript -e 'options(warn = 1); invisible(gms::codeCheck(strict = TRUE, interactive = TRUE)); testthat::test_dir("tests/testthat"); message("Do not forget to commit changes done by codeCheck to not_used.txt files");'
 
 test-coupled:    ## Test if the coupling with MAgPIE works. Takes significantly
                  ## longer than 60 minutes to run and needs slurm and magpie

tests/testthat/test_01-codeCheck.R

@@ -7,7 +7,7 @@
 test_that("GAMS code follows the coding etiquette", {
   # have to run this via localSystem2 so that it uses the renv, where gms
   # is actually installed.
-  codecheckcode <- "'invisible(gms::codeCheck(strict = TRUE)); if (! is.null(warnings())) stop(warnings())'"
+  codecheckcode <- "'options(warn = 1); invisible(gms::codeCheck(strict = TRUE));'"
   output <- localSystem2("Rscript", c("-e", codecheckcode))
   printIfFailed(output)
   expectSuccessStatus(output)