The PostgreSQL code has really confusing indents. For the help for programmers, there is a tool named pgindent located at src/tools/pgindent. Earlier it was written in C and has had a set of dependencies, the installation was tedious. Now, it is rewritten in Perl and downloads all dependencies itself. The only requirement is pg_config on PATH, to run it in such way use --build option. The tool clones git repo pg_bsd_indent, downloads typedefs, indents and then deletes repo. If the previous run was not successful, the repository will stay in the src/tools/pgindent/pg_bsd_indent and will cause an error for git clone command, just remove it. The other point it generates files for typedefs, do not forget to delete them before commit. To indent single file run:

src/tools/pgindent/pgindent --build filename

To indent all files in current directory and subdirectories:

src/tools/pgindent/pgindent --build

There are also pgperltidy for Perl.