1SPECIFYING REVISIONS 2-------------------- 3 4A revision parameter '<rev>' typically, but not necessarily, names a 5commit object. It uses what is called an 'extended SHA-1' 6syntax. Here are various ways to spell object names. The 7ones listed near the end of this list name trees and 8blobs contained in a commit. 9 10NOTE: This document shows the "raw" syntax as seen by git. The shell 11and other UIs might require additional quoting to protect special 12characters and to avoid word splitting. 13 14'<sha1>', e.g. 'dae86e1950b1277e545cee180551750029cfe735', 'dae86e':: 15 The full SHA-1 object name (40-byte hexadecimal string), or 16 a leading substring that is unique within the repository. 17 E.g. dae86e1950b1277e545cee180551750029cfe735 and dae86e both 18 name the same commit object if there is no other object in 19 your repository whose object name starts with dae86e. 20 21'<describeOutput>', e.g. 'v1.7.4.2-679-g3bee7fb':: 22 Output from `git describe`; i.e. a closest tag, optionally 23 followed by a dash and a number of commits, followed by a dash, a 24 'g', and an abbreviated object name. 25 26'<refname>', e.g. 'master', 'heads/master', 'refs/heads/master':: 27 A symbolic ref name. E.g. 'master' typically means the commit 28 object referenced by 'refs/heads/master'. If you 29 happen to have both 'heads/master' and 'tags/master', you can 30 explicitly say 'heads/master' to tell Git which one you mean. 31 When ambiguous, a '<refname>' is disambiguated by taking the 32 first match in the following rules: 33 34 . If '$GIT_DIR/<refname>' exists, that is what you mean (this is usually 35 useful only for `HEAD`, `FETCH_HEAD`, `ORIG_HEAD`, `MERGE_HEAD` 36 and `CHERRY_PICK_HEAD`); 37 38 . otherwise, 'refs/<refname>' if it exists; 39 40 . otherwise, 'refs/tags/<refname>' if it exists; 41 42 . otherwise, 'refs/heads/<refname>' if it exists; 43 44 . otherwise, 'refs/remotes/<refname>' if it exists; 45 46 . otherwise, 'refs/remotes/<refname>/HEAD' if it exists. 47+ 48`HEAD` names the commit on which you based the changes in the working tree. 49`FETCH_HEAD` records the branch which you fetched from a remote repository 50with your last `git fetch` invocation. 51`ORIG_HEAD` is created by commands that move your `HEAD` in a drastic 52way, to record the position of the `HEAD` before their operation, so that 53you can easily change the tip of the branch back to the state before you ran 54them. 55`MERGE_HEAD` records the commit(s) which you are merging into your branch 56when you run `git merge`. 57`CHERRY_PICK_HEAD` records the commit which you are cherry-picking 58when you run `git cherry-pick`. 59+ 60Note that any of the 'refs/*' cases above may come either from 61the '$GIT_DIR/refs' directory or from the '$GIT_DIR/packed-refs' file. 62While the ref name encoding is unspecified, UTF-8 is preferred as 63some output processing may assume ref names in UTF-8. 64 65'@':: 66 '@' alone is a shortcut for `HEAD`. 67 68'[<refname>]@{<date>}', e.g. 'master@\{yesterday\}', 'HEAD@{5 minutes ago}':: 69 A ref followed by the suffix '@' with a date specification 70 enclosed in a brace 71 pair (e.g. '\{yesterday\}', '{1 month 2 weeks 3 days 1 hour 1 72 second ago}' or '{1979-02-26 18:30:00}') specifies the value 73 of the ref at a prior point in time. This suffix may only be 74 used immediately following a ref name and the ref must have an 75 existing log ('$GIT_DIR/logs/<ref>'). Note that this looks up the state 76 of your *local* ref at a given time; e.g., what was in your local 77 'master' branch last week. If you want to look at commits made during 78 certain times, see `--since` and `--until`. 79 80'<refname>@{<n>}', e.g. 'master@\{1\}':: 81 A ref followed by the suffix '@' with an ordinal specification 82 enclosed in a brace pair (e.g. '\{1\}', '\{15\}') specifies 83 the n-th prior value of that ref. For example 'master@\{1\}' 84 is the immediate prior value of 'master' while 'master@\{5\}' 85 is the 5th prior value of 'master'. This suffix may only be used 86 immediately following a ref name and the ref must have an existing 87 log ('$GIT_DIR/logs/<refname>'). 88 89'@{<n>}', e.g. '@\{1\}':: 90 You can use the '@' construct with an empty ref part to get at a 91 reflog entry of the current branch. For example, if you are on 92 branch 'blabla' then '@\{1\}' means the same as 'blabla@\{1\}'. 93 94'@{-<n>}', e.g. '@{-1}':: 95 The construct '@{-<n>}' means the <n>th branch/commit checked out 96 before the current one. 97 98'[<branchname>]@\{upstream\}', e.g. 'master@\{upstream\}', '@\{u\}':: 99 The suffix '@\{upstream\}' to a branchname (short form '<branchname>@\{u\}') 100 refers to the branch that the branch specified by branchname is set to build on 101 top of (configured with `branch.<name>.remote` and 102 `branch.<name>.merge`). A missing branchname defaults to the 103 current one. These suffixes are also accepted when spelled in uppercase, and 104 they mean the same thing no matter the case. 105 106'[<branchname>]@\{push\}', e.g. 'master@\{push\}', '@\{push\}':: 107 The suffix '@\{push}' reports the branch "where we would push to" if 108 `git push` were run while `branchname` was checked out (or the current 109 `HEAD` if no branchname is specified). Since our push destination is 110 in a remote repository, of course, we report the local tracking branch 111 that corresponds to that branch (i.e., something in 'refs/remotes/'). 112+ 113Here's an example to make it more clear: 114+ 115------------------------------ 116$ git config push.default current 117$ git config remote.pushdefault myfork 118$ git checkout -b mybranch origin/master 119 120$ git rev-parse --symbolic-full-name @{upstream} 121refs/remotes/origin/master 122 123$ git rev-parse --symbolic-full-name @{push} 124refs/remotes/myfork/mybranch 125------------------------------ 126+ 127Note in the example that we set up a triangular workflow, where we pull 128from one location and push to another. In a non-triangular workflow, 129'@\{push}' is the same as '@\{upstream}', and there is no need for it. 130+ 131This suffix is also accepted when spelled in uppercase, and means the same 132thing no matter the case. 133 134'<rev>{caret}[<n>]', e.g. 'HEAD{caret}, v1.5.1{caret}0':: 135 A suffix '{caret}' to a revision parameter means the first parent of 136 that commit object. '{caret}<n>' means the <n>th parent (i.e. 137 '<rev>{caret}' 138 is equivalent to '<rev>{caret}1'). As a special rule, 139 '<rev>{caret}0' means the commit itself and is used when '<rev>' is the 140 object name of a tag object that refers to a commit object. 141 142'<rev>{tilde}<n>', e.g. 'master{tilde}3':: 143 A suffix '{tilde}<n>' to a revision parameter means the commit 144 object that is the <n>th generation ancestor of the named 145 commit object, following only the first parents. I.e. '<rev>{tilde}3' is 146 equivalent to '<rev>{caret}{caret}{caret}' which is equivalent to 147 '<rev>{caret}1{caret}1{caret}1'. See below for an illustration of 148 the usage of this form. 149 150'<rev>{caret}{<type>}', e.g. 'v0.99.8{caret}\{commit\}':: 151 A suffix '{caret}' followed by an object type name enclosed in 152 brace pair means dereference the object at '<rev>' recursively until 153 an object of type '<type>' is found or the object cannot be 154 dereferenced anymore (in which case, barf). 155 For example, if '<rev>' is a commit-ish, '<rev>{caret}\{commit\}' 156 describes the corresponding commit object. 157 Similarly, if '<rev>' is a tree-ish, '<rev>{caret}\{tree\}' 158 describes the corresponding tree object. 159 '<rev>{caret}0' 160 is a short-hand for '<rev>{caret}\{commit\}'. 161+ 162'<rev>{caret}\{object\}' can be used to make sure '<rev>' names an 163object that exists, without requiring '<rev>' to be a tag, and 164without dereferencing '<rev>'; because a tag is already an object, 165it does not have to be dereferenced even once to get to an object. 166+ 167'<rev>{caret}\{tag\}' can be used to ensure that '<rev>' identifies an 168existing tag object. 169 170'<rev>{caret}{}', e.g. 'v0.99.8{caret}{}':: 171 A suffix '{caret}' followed by an empty brace pair 172 means the object could be a tag, 173 and dereference the tag recursively until a non-tag object is 174 found. 175 176'<rev>{caret}{/<text>}', e.g. 'HEAD^{/fix nasty bug}':: 177 A suffix '{caret}' to a revision parameter, followed by a brace 178 pair that contains a text led by a slash, 179 is the same as the ':/fix nasty bug' syntax below except that 180 it returns the youngest matching commit which is reachable from 181 the '<rev>' before '{caret}'. 182 183':/<text>', e.g. ':/fix nasty bug':: 184 A colon, followed by a slash, followed by a text, names 185 a commit whose commit message matches the specified regular expression. 186 This name returns the youngest matching commit which is 187 reachable from any ref. The regular expression can match any part of the 188 commit message. To match messages starting with a string, one can use 189 e.g. ':/^foo'. The special sequence ':/!' is reserved for modifiers to what 190 is matched. ':/!-foo' performs a negative match, while ':/!!foo' matches a 191 literal '!' character, followed by 'foo'. Any other sequence beginning with 192 ':/!' is reserved for now. 193 Depending on the given text, the shell's word splitting rules might 194 require additional quoting. 195 196'<rev>:<path>', e.g. 'HEAD:README', ':README', 'master:./README':: 197 A suffix ':' followed by a path names the blob or tree 198 at the given path in the tree-ish object named by the part 199 before the colon. 200 ':path' (with an empty part before the colon) 201 is a special case of the syntax described next: content 202 recorded in the index at the given path. 203 A path starting with './' or '../' is relative to the current working directory. 204 The given path will be converted to be relative to the working tree's root directory. 205 This is most useful to address a blob or tree from a commit or tree that has 206 the same tree structure as the working tree. 207 208':<n>:<path>', e.g. ':0:README', ':README':: 209 A colon, optionally followed by a stage number (0 to 3) and a 210 colon, followed by a path, names a blob object in the 211 index at the given path. A missing stage number (and the colon 212 that follows it) names a stage 0 entry. During a merge, stage 213 1 is the common ancestor, stage 2 is the target branch's version 214 (typically the current branch), and stage 3 is the version from 215 the branch which is being merged. 216 217Here is an illustration, by Jon Loeliger. Both commit nodes B 218and C are parents of commit node A. Parent commits are ordered 219left-to-right. 220 221........................................ 222G H I J 223 \ / \ / 224 D E F 225 \ | / \ 226 \ | / | 227 \|/ | 228 B C 229 \ / 230 \ / 231 A 232........................................ 233 234 A = = A^0 235 B = A^ = A^1 = A~1 236 C = A^2 = A^2 237 D = A^^ = A^1^1 = A~2 238 E = B^2 = A^^2 239 F = B^3 = A^^3 240 G = A^^^ = A^1^1^1 = A~3 241 H = D^2 = B^^2 = A^^^2 = A~2^2 242 I = F^ = B^3^ = A^^3^ 243 J = F^2 = B^3^2 = A^^3^2 244 245 246SPECIFYING RANGES 247----------------- 248 249History traversing commands such as `git log` operate on a set 250of commits, not just a single commit. 251 252For these commands, 253specifying a single revision, using the notation described in the 254previous section, means the set of commits `reachable` from the given 255commit. 256 257A commit's reachable set is the commit itself and the commits in 258its ancestry chain. 259 260 261Commit Exclusions 262~~~~~~~~~~~~~~~~~ 263 264'{caret}<rev>' (caret) Notation:: 265 To exclude commits reachable from a commit, a prefix '{caret}' 266 notation is used. E.g. '{caret}r1 r2' means commits reachable 267 from 'r2' but exclude the ones reachable from 'r1' (i.e. 'r1' and 268 its ancestors). 269 270Dotted Range Notations 271~~~~~~~~~~~~~~~~~~~~~~ 272 273The '..' (two-dot) Range Notation:: 274 The '{caret}r1 r2' set operation appears so often that there is a shorthand 275 for it. When you have two commits 'r1' and 'r2' (named according 276 to the syntax explained in SPECIFYING REVISIONS above), you can ask 277 for commits that are reachable from r2 excluding those that are reachable 278 from r1 by '{caret}r1 r2' and it can be written as 'r1..r2'. 279 280The '...' (three-dot) Symmetric Difference Notation:: 281 A similar notation 'r1\...r2' is called symmetric difference 282 of 'r1' and 'r2' and is defined as 283 'r1 r2 --not $(git merge-base --all r1 r2)'. 284 It is the set of commits that are reachable from either one of 285 'r1' (left side) or 'r2' (right side) but not from both. 286 287In these two shorthand notations, you can omit one end and let it default to HEAD. 288For example, 'origin..' is a shorthand for 'origin..HEAD' and asks "What 289did I do since I forked from the origin branch?" Similarly, '..origin' 290is a shorthand for 'HEAD..origin' and asks "What did the origin do since 291I forked from them?" Note that '..' would mean 'HEAD..HEAD' which is an 292empty range that is both reachable and unreachable from HEAD. 293 294Other <rev>{caret} Parent Shorthand Notations 295~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 296Three other shorthands exist, particularly useful for merge commits, 297for naming a set that is formed by a commit and its parent commits. 298 299The 'r1{caret}@' notation means all parents of 'r1'. 300 301The 'r1{caret}!' notation includes commit 'r1' but excludes all of its parents. 302By itself, this notation denotes the single commit 'r1'. 303 304The '<rev>{caret}-[<n>]' notation includes '<rev>' but excludes the <n>th 305parent (i.e. a shorthand for '<rev>{caret}<n>..<rev>'), with '<n>' = 1 if 306not given. This is typically useful for merge commits where you 307can just pass '<commit>{caret}-' to get all the commits in the branch 308that was merged in merge commit '<commit>' (including '<commit>' 309itself). 310 311While '<rev>{caret}<n>' was about specifying a single commit parent, these 312three notations also consider its parents. For example you can say 313'HEAD{caret}2{caret}@', however you cannot say 'HEAD{caret}@{caret}2'. 314 315Revision Range Summary 316---------------------- 317 318'<rev>':: 319 Include commits that are reachable from <rev> (i.e. <rev> and its 320 ancestors). 321 322'{caret}<rev>':: 323 Exclude commits that are reachable from <rev> (i.e. <rev> and its 324 ancestors). 325 326'<rev1>..<rev2>':: 327 Include commits that are reachable from <rev2> but exclude 328 those that are reachable from <rev1>. When either <rev1> or 329 <rev2> is omitted, it defaults to `HEAD`. 330 331'<rev1>\...<rev2>':: 332 Include commits that are reachable from either <rev1> or 333 <rev2> but exclude those that are reachable from both. When 334 either <rev1> or <rev2> is omitted, it defaults to `HEAD`. 335 336'<rev>{caret}@', e.g. 'HEAD{caret}@':: 337 A suffix '{caret}' followed by an at sign is the same as listing 338 all parents of '<rev>' (meaning, include anything reachable from 339 its parents, but not the commit itself). 340 341'<rev>{caret}!', e.g. 'HEAD{caret}!':: 342 A suffix '{caret}' followed by an exclamation mark is the same 343 as giving commit '<rev>' and then all its parents prefixed with 344 '{caret}' to exclude them (and their ancestors). 345 346'<rev>{caret}-<n>', e.g. 'HEAD{caret}-, HEAD{caret}-2':: 347 Equivalent to '<rev>{caret}<n>..<rev>', with '<n>' = 1 if not 348 given. 349 350Here are a handful of examples using the Loeliger illustration above, 351with each step in the notation's expansion and selection carefully 352spelt out: 353 354.... 355 Args Expanded arguments Selected commits 356 D G H D 357 D F G H I J D F 358 ^G D H D 359 ^D B E I J F B 360 ^D B C E I J F B C 361 C I J F C 362 B..C = ^B C C 363 B...C = B ^F C G H D E B C 364 B^- = B^..B 365 = ^B^1 B E I J F B 366 C^@ = C^1 367 = F I J F 368 B^@ = B^1 B^2 B^3 369 = D E F D G H E F I J 370 C^! = C ^C^@ 371 = C ^C^1 372 = C ^F C 373 B^! = B ^B^@ 374 = B ^B^1 ^B^2 ^B^3 375 = B ^D ^E ^F B 376 F^! D = F ^I ^J D G H D F 377....