title: "Automation: Test drive make" author: "Shaun Jackman, Jenny Bryan" output: html_document: toc: true toc_depth: 3

pandoc_args: "--preserve-tabs"

Before we use make for real work, we want to prove beyond a shadow of a doubt that it's installed and findable from RStudio and/or the shell.

Create a temporary RStudio Project

You can delete this project after this test drive, so don't sweat too much about what you name it or where you put it.

• Create an RStudio project: File > New Project
• Create a new text file: File > New File > Text File
• We are about to write our first Makefile!

But first ...

Disable "insert spaces for tab"

Tabs are very meaningful in Makefiles, so it's important to make sure your text editor is not "helpfully" but silently converting tabs to spaces.

Here's how to disable this in RStudio.

• Global setting: Tools > Global Options... > Code editing. Make sure "insert spaces for tab" is unchecked.
• Project-specific setting: Tools > Project Options... > Code editing. Make sure "insert spaces for tab" is unchecked.

RStudio can reveal information about the whitespace in a file: RStudio > Preferences... > Code editing > Show whitespace characters. When in doubt, make darn sure your Makefile is indented with tabs and not spaces!

Write a toy Makefile

Type or paste this into your new text file. Make sure the indentation before @echo is always a tab! Save as Makefile:

all:
    @echo Build all

clean:
    @echo Clean all

Configure this Rstudio Project to use make

Select Build > Configure Build Tools > Build Tools > Project build tools > Makefile.

This will make a new tab and buttons and menus available in RStudio, usually in the upper right-hand pane, similar to the Git stuff.

Run make via RStudio

Select Build > Build All (the hammer icon).

The result and any error messages should appear under the Build tab.

Hopefully you will see this:

Build all

If you see something like this:

Makefile:2: *** missing separator.  Stop.

you probably have spaces instead of tabs as indentation. Fix that and try again.

RStudio offers these buttons or menu items to run things from your Makefile:

• Build All runs make all, as we just saw
• Clean All runs make clean
• Clean and Rebuild runs make clean all

For these menu items to work, your Makefile needs to have targets named all and clean. These non-file targets are called phony targets.

You should be able to select Build > More > Clean All and get this:

Clean all

You should be able to select Build > More > Clean and Rebuild and get this:

Clean all
Build all

This proves that make is installed and working from RStudio.

Run make from the shell

RStudio only provides access to a very limited bit of make -- it's even more limited than the RStudio Git client. In the long run, it's important to be able to run make from the shell.

• Select Tools > Shell

• Run

  make clean
  make all
  make clean all
  

You should be seeing similar output as you saw in the Build tab of RStudio.

If you are not, are you getting the error message that's characteristic of a "spaces instead of tabs" problem? Or does it look more like make or other commands aren't being found? If the latter, go back to the Windows installation page or reach out to the course staff.