From Fedora Project Wiki

Proposal

Alter the "Spec Legibility" section to indicate that the tab width in spec files should be eight spaces.

Current guideline

All Fedora Package Spec Files must be legible. If the reviewer is unable to read the spec file, it will be impossible to perform a review. Fedora Spec files are not the place for entries into the Obfuscated Code Contest.

Proposed new guideline

All Fedora Package Spec Files must be legible and the tab width should be set to eight spaces. If the reviewer is unable to read the spec file, it will be impossible to perform a review. Fedora Spec files are not the place for entries into the Obfuscated Code Contest.

Rationale

Fedora is not anyone's personal repository; packages are assumed to be maintained by multiple people. As we have no reasonable way to specify tab width per spec file, specs should be written to a reasonable common denominator. Just as we ask folks to put aside regional differences and use American English for summaries and descriptions, we should ask them to put aside weird personal conventions for tab width and use something reasonably standard.