subrepo: avoids empty commit when .hgsubstate is dirty (issue2403) This patch avoids empty commit when .hgsubstate is dirty. Empty commit was caused by .hgsubstate being updated back to the state of the working copy parent when committing, if a user had changed it manually and not made any changes in subrepositories. The subrepository state from the working copies parent is compared with the state calculated as a result of trying to commit the subrepositories. If the two states are the same, then return None otherwise the commit is just done. The line: "committing subrepository x" will be written if there is nothing committed, but .hgsubstate is dirty for x subrepository.