hg-core: minor docstring update (D8958#inline-14991 followup) Differential Revision: https://phab.mercurial-scm.org/D9097

hg-core: minor code style change (D8958#inline-14986 followup) Differential Revision: https://phab.mercurial-scm.org/D9096

hg-core: Explain offset override of first revision (D8958#inline-14992 followup) Differential Revision: https://phab.mercurial-scm.org/D9095

hg-core: minor code style change (D8958#inline-14993 followup) Differential Revision: https://phab.mercurial-scm.org/D9083

changing-files: move default constructor value to None According to Augie Fackler, using tuple as default value confuse PyType when actual values are passed at init time. Differential Revision: https://phab.mercurial-scm.org/D9086

rust: format with rustfmt I suppose I ran the formatter on the tip but not on every patch. Differential Revision: https://phab.mercurial-scm.org/D9093

merge: store cases when a file is absent post merge in commitinfo Some merges can result in file being absent form working directory. This can be one of file was kept deleted or file was removed by merge code. User might revert the file back before committing. In such cases we will like to have better handling and create new filenodes. We store this info in mergestate as commitinfo so that we can use it while committing to create new filenode if required. Differential Revision: https://phab.mercurial-scm.org/D9003

tests: add some more debugmergestate calls in `test-merge-criss-cross.t` Differential Revision: https://phab.mercurial-scm.org/D9029