#require no-reposimplestore

  $ cat >> $HGRCPATH << EOF

  > [extensions]

  > share =

  > EOF

store and revlogv1 are required in source

  $ hg --config format.usestore=false init no-store

  $ hg -R no-store debugupgraderepo

  abort: cannot upgrade repository; requirement missing: store

  [255]

  $ hg init no-revlogv1

  $ cat > no-revlogv1/.hg/requires << EOF

  > dotencode

  > fncache

  > generaldelta

  > store

  > EOF

  $ hg -R no-revlogv1 debugupgraderepo

  abort: cannot upgrade repository; requirement missing: revlogv1

  [255]

Cannot upgrade shared repositories

  $ hg init share-parent

  $ hg -q share share-parent share-child

  $ hg -R share-child debugupgraderepo

  abort: cannot upgrade repository; unsupported source requirement: shared

  [255]

Do not yet support upgrading treemanifest repos

  $ hg --config experimental.treemanifest=true init treemanifest

  $ hg -R treemanifest debugupgraderepo

  abort: cannot upgrade repository; unsupported source requirement: treemanifest

  [255]

Cannot add treemanifest requirement during upgrade

  $ hg init disallowaddedreq

  $ hg -R disallowaddedreq --config experimental.treemanifest=true debugupgraderepo

  abort: cannot upgrade repository; do not support adding requirement: treemanifest

  [255]

An upgrade of a repository created with recommended settings only suggests optimizations

  $ hg init empty

  $ cd empty

  $ hg debugformat

  format-variant     repo

  fncache:            yes

  dotencode:          yes

  generaldelta:       yes

  sparserevlog:       yes

  sidedata:            no

  persistent-nodemap:  no

  copies-sdc:          no

  plain-cl-delta:     yes

  compression:        zlib

  compression-level:  default

  $ hg debugformat --verbose

  format-variant     repo config default

  fncache:            yes    yes     yes

  dotencode:          yes    yes     yes

  generaldelta:       yes    yes     yes

  sparserevlog:       yes    yes     yes

  sidedata:            no     no      no

  persistent-nodemap:  no     no      no

  copies-sdc:          no     no      no

  plain-cl-delta:     yes    yes     yes

  compression:        zlib   zlib    zlib

  compression-level:  default default default

  $ hg debugformat --verbose --config format.usefncache=no

  format-variant     repo config default

  fncache:            yes     no     yes

  dotencode:          yes     no     yes

  generaldelta:       yes    yes     yes

  sparserevlog:       yes    yes     yes

  sidedata:            no     no      no

  persistent-nodemap:  no     no      no

  copies-sdc:          no     no      no

  plain-cl-delta:     yes    yes     yes

  compression:        zlib   zlib    zlib

  compression-level:  default default default

  $ hg debugformat --verbose --config format.usefncache=no --color=debug

  format-variant     repo config default

  [formatvariant.name.mismatchconfig|fncache:           ][formatvariant.repo.mismatchconfig| yes][formatvariant.config.special|     no][formatvariant.default|     yes]

  [formatvariant.name.mismatchconfig|dotencode:         ][formatvariant.repo.mismatchconfig| yes][formatvariant.config.special|     no][formatvariant.default|     yes]

  [formatvariant.name.uptodate|generaldelta:      ][formatvariant.repo.uptodate| yes][formatvariant.config.default|    yes][formatvariant.default|     yes]

  [formatvariant.name.uptodate|sparserevlog:      ][formatvariant.repo.uptodate| yes][formatvariant.config.default|    yes][formatvariant.default|     yes]

  [formatvariant.name.uptodate|sidedata:          ][formatvariant.repo.uptodate|  no][formatvariant.config.default|     no][formatvariant.default|      no]

  [formatvariant.name.uptodate|persistent-nodemap:][formatvariant.repo.uptodate|  no][formatvariant.config.default|     no][formatvariant.default|      no]

  [formatvariant.name.uptodate|copies-sdc:        ][formatvariant.repo.uptodate|  no][formatvariant.config.default|     no][formatvariant.default|      no]

  [formatvariant.name.uptodate|plain-cl-delta:    ][formatvariant.repo.uptodate| yes][formatvariant.config.default|    yes][formatvariant.default|     yes]

  [formatvariant.name.uptodate|compression:       ][formatvariant.repo.uptodate| zlib][formatvariant.config.default|   zlib][formatvariant.default|    zlib]

  [formatvariant.name.uptodate|compression-level: ][formatvariant.repo.uptodate| default][formatvariant.config.default| default][formatvariant.default| default]

  $ hg debugformat -Tjson

  [

   {

    "config": true,

    "default": true,

    "name": "fncache",

    "repo": true

   },

   {

    "config": true,

    "default": true,

    "name": "dotencode",

    "repo": true

   },

   {

    "config": true,

    "default": true,

    "name": "generaldelta",

    "repo": true

   },

   {

    "config": true,

    "default": true,

    "name": "sparserevlog",

    "repo": true

   },

   {

    "config": false,

    "default": false,

    "name": "sidedata",

    "repo": false

   },

   {

    "config": false,

    "default": false,

    "name": "persistent-nodemap",

    "repo": false

   },

   {

    "config": false,

    "default": false,

    "name": "copies-sdc",

    "repo": false

   },

   {

    "config": true,

    "default": true,

    "name": "plain-cl-delta",

    "repo": true

   },

   {

    "config": "zlib",

    "default": "zlib",

    "name": "compression",

    "repo": "zlib"

   },

   {

    "config": "default",

    "default": "default",

    "name": "compression-level",

    "repo": "default"

   }

  ]

  $ hg debugupgraderepo

  (no feature deficiencies found in existing repository)

  performing an upgrade with "--run" will make the following changes:

  requirements

     preserved: dotencode, fncache, generaldelta, revlogv1, sparserevlog, store

  additional optimizations are available by specifying "--optimize <name>":

  re-delta-parent

     deltas within internal storage will be recalculated to choose an optimal base revision where this was not already done; the size of the repository may shrink and various operations may become faster; the first time this optimization is performed could slow down upgrade execution considerably; subsequent invocations should not run noticeably slower

  re-delta-multibase

     deltas within internal storage will be recalculated against multiple base revision and the smallest difference will be used; the size of the repository may shrink significantly when there are many merges; this optimization will slow down execution in proportion to the number of merges in the repository and the amount of files in the repository; this slow down should not be significant unless there are tens of thousands of files and thousands of merges

  re-delta-all

     deltas within internal storage will always be recalculated without reusing prior deltas; this will likely make execution run several times slower; this optimization is typically not needed

  re-delta-fulladd

     every revision will be re-added as if it was new content. It will go through the full storage mechanism giving extensions a chance to process it (eg. lfs). This is similar to "re-delta-all" but even slower since more logic is involved.

  $ hg debugupgraderepo --quiet

  requirements

     preserved: dotencode, fncache, generaldelta, revlogv1, sparserevlog, store

--optimize can be used to add optimizations

  $ hg debugupgrade --optimize redeltaparent

  (no feature deficiencies found in existing repository)

  performing an upgrade with "--run" will make the following changes:

  requirements

     preserved: dotencode, fncache, generaldelta, revlogv1, sparserevlog, store

  optimisations: re-delta-parent

  re-delta-parent

     deltas within internal storage will choose a new base revision if needed

  additional optimizations are available by specifying "--optimize <name>":

  re-delta-multibase

     deltas within internal storage will be recalculated against multiple base revision and the smallest difference will be used; the size of the repository may shrink significantly when there are many merges; this optimization will slow down execution in proportion to the number of merges in the repository and the amount of files in the repository; this slow down should not be significant unless there are tens of thousands of files and thousands of merges

  re-delta-all

     deltas within internal storage will always be recalculated without reusing prior deltas; this will likely make execution run several times slower; this optimization is typically not needed

  re-delta-fulladd

     every revision will be re-added as if it was new content. It will go through the full storage mechanism giving extensions a chance to process it (eg. lfs). This is similar to "re-delta-all" but even slower since more logic is involved.

modern form of the option

  $ hg debugupgrade --optimize re-delta-parent

  (no feature deficiencies found in existing repository)

  performing an upgrade with "--run" will make the following changes:

  requirements

     preserved: dotencode, fncache, generaldelta, revlogv1, sparserevlog, store

  optimisations: re-delta-parent

  re-delta-parent

     deltas within internal storage will choose a new base revision if needed

  additional optimizations are available by specifying "--optimize <name>":

  re-delta-multibase

     deltas within internal storage will be recalculated against multiple base revision and the smallest difference will be used; the size of the repository may shrink significantly when there are many merges; this optimization will slow down execution in proportion to the number of merges in the repository and the amount of files in the repository; this slow down should not be significant unless there are tens of thousands of files and thousands of merges

  re-delta-all

     deltas within internal storage will always be recalculated without reusing prior deltas; this will likely make execution run several times slower; this optimization is typically not needed

  re-delta-fulladd

     every revision will be re-added as if it was new content. It will go through the full storage mechanism giving extensions a chance to process it (eg. lfs). This is similar to "re-delta-all" but even slower since more logic is involved.

  $ hg debugupgrade --optimize re-delta-parent --quiet

  requirements

     preserved: dotencode, fncache, generaldelta, revlogv1, sparserevlog, store

  optimisations: re-delta-parent

unknown optimization:

  $ hg debugupgrade --optimize foobar

  abort: unknown optimization action requested: foobar

  (run without arguments to see valid optimizations)

  [255]

Various sub-optimal detections work

  $ cat > .hg/requires << EOF

  > revlogv1

  > store

  > EOF

  $ hg debugformat

  format-variant     repo

  fncache:             no

  dotencode:           no

  generaldelta:        no

  sparserevlog:        no

  sidedata:            no

  persistent-nodemap:  no

  copies-sdc:          no

  plain-cl-delta:     yes

  compression:        zlib

  compression-level:  default

  $ hg debugformat --verbose

  format-variant     repo config default

  fncache:             no    yes     yes

  dotencode:           no    yes     yes

  generaldelta:        no    yes     yes

  sparserevlog:        no    yes     yes

  sidedata:            no     no      no

  persistent-nodemap:  no     no      no

  copies-sdc:          no     no      no

  plain-cl-delta:     yes    yes     yes

  compression:        zlib   zlib    zlib

  compression-level:  default default default

  $ hg debugformat --verbose --config format.usegeneraldelta=no

  format-variant     repo config default

  fncache:             no    yes     yes

  dotencode:           no    yes     yes

  generaldelta:        no     no     yes

  sparserevlog:        no     no     yes

  sidedata:            no     no      no

  persistent-nodemap:  no     no      no

  copies-sdc:          no     no      no

  plain-cl-delta:     yes    yes     yes

  compression:        zlib   zlib    zlib

  compression-level:  default default default

  $ hg debugformat --verbose --config format.usegeneraldelta=no --color=debug

  format-variant     repo config default

  [formatvariant.name.mismatchconfig|fncache:           ][formatvariant.repo.mismatchconfig|  no][formatvariant.config.default|    yes][formatvariant.default|     yes]

  [formatvariant.name.mismatchconfig|dotencode:         ][formatvariant.repo.mismatchconfig|  no][formatvariant.config.default|    yes][formatvariant.default|     yes]

  [formatvariant.name.mismatchdefault|generaldelta:      ][formatvariant.repo.mismatchdefault|  no][formatvariant.config.special|     no][formatvariant.default|     yes]

  [formatvariant.name.mismatchdefault|sparserevlog:      ][formatvariant.repo.mismatchdefault|  no][formatvariant.config.special|     no][formatvariant.default|     yes]

  [formatvariant.name.uptodate|sidedata:          ][formatvariant.repo.uptodate|  no][formatvariant.config.default|     no][formatvariant.default|      no]

  [formatvariant.name.uptodate|persistent-nodemap:][formatvariant.repo.uptodate|  no][formatvariant.config.default|     no][formatvariant.default|      no]

  [formatvariant.name.uptodate|copies-sdc:        ][formatvariant.repo.uptodate|  no][formatvariant.config.default|     no][formatvariant.default|      no]

  [formatvariant.name.uptodate|plain-cl-delta:    ][formatvariant.repo.uptodate| yes][formatvariant.config.default|    yes][formatvariant.default|     yes]

  [formatvariant.name.uptodate|compression:       ][formatvariant.repo.uptodate| zlib][formatvariant.config.default|   zlib][formatvariant.default|    zlib]

  [formatvariant.name.uptodate|compression-level: ][formatvariant.repo.uptodate| default][formatvariant.config.default| default][formatvariant.default| default]

  $ hg debugupgraderepo

  repository lacks features recommended by current config options:

  fncache

     long and reserved filenames may not work correctly; repository performance is sub-optimal