[analog31]

An interesting thing about things like version control and test automation is that they are almost like "meta interpreters" that interpret your code, but do so for purposes other than executing it. Syntax checking and linting come to mind too. Those things are possible, not so much because the program is in text format, but because it's in an open format that anybody can parse.

If a visual programming language stored its programs in a human readable or at least open format, then it would be possible for people to create those tools for it. But then, people would start writing and editing the program directly in its storage format, and it would cease to be visual programming.