Add better documentation to DirCacheCheckout Change-Id: I282b702d9e4cb19063d8e9503604538f80e955b7 Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheCheckout.java b/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheCheckout.java index 7629de6..292206e 100644 --- a/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheCheckout.java +++ b/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheCheckout.java
@@ -683,6 +683,8 @@ void processEntry(CanonicalTreeParser h, CanonicalTreeParser m, } if (i == null) { + // Nothing in Index + // At least one of Head, Index, Merge is not empty // make sure not to overwrite untracked files if (f != null) { // A submodule is not a file. We should ignore it @@ -711,17 +713,37 @@ void processEntry(CanonicalTreeParser h, CanonicalTreeParser m, */ if (h == null) + // Nothing in Head + // Nothing in Index + // At least one of Head, Index, Merge is not empty + // -> only Merge contains something for this path. Use it! + // Potentially update the file update(name, mId, mMode); // 1 else if (m == null) + // Nothing in Merge + // Something in Head + // Nothing in Index + // -> only Head contains something for this path and it should + // be deleted. Potentially removes the file! remove(name); // 2 else { // 3 + // Something in Merge + // Something in Head + // Nothing in Index + // -> Head and Merge contain something (maybe not the same) and + // in the index there is nothing (e.g. 'git rm ...' was + // called before). Ignore the cached deletion and use what we + // find in Merge. Potentially updates the file. if (equalIdAndMode(hId, hMode, mId, mMode)) keep(dce); else conflict(name, dce, h, m); } } else { + // Something in Index if (h == null) { + // Nothing in Head + // Something in Index /** * <pre> * clean I==H I==M H M Result @@ -737,17 +759,54 @@ else if (m == null) */ if (m == null || equalIdAndMode(mId, mMode, iId, iMode)) { + // Merge contains nothing or the same as Index + // Nothing in Head + // Something in Index if (m==null && walk.isDirectoryFileConflict()) { + // Nothing in Merge and current path is part of + // File/Folder conflict + // Nothing in Head + // Something in Index if (dce != null && (f == null || f.isModified(dce, true))) + // No file or file is dirty + // Nothing in Merge and current path is part of + // File/Folder conflict + // Nothing in Head + // Something in Index + // -> File folder conflict and Merge wants this + // path to be removed. Since the file is dirty + // report a conflict conflict(name, dce, h, m); else + // A file is present and file is not dirty + // Nothing in Merge and current path is part of + // File/Folder conflict + // Nothing in Head + // Something in Index + // -> File folder conflict and Merge wants this path + // to be removed. Since the file is not dirty remove + // file and index entry remove(name); } else + // Something in Merge or current path is not part of + // File/Folder conflict + // Merge contains nothing or the same as Index + // Nothing in Head + // Something in Index + // -> Merge contains nothing new. Keep the index. keep(dce); } else + // Merge contains something and it is not the same as Index + // Nothing in Head + // Something in Index + // -> Index contains something new (different from Head) + // and Merge is different from Index. Report a conflict conflict(name, dce, h, m); } else if (m == null) { + // Nothing in Merge + // Something in Head + // Something in Index /** * <pre> @@ -761,36 +820,115 @@ else if (m == null) */ if (iMode == FileMode.GITLINK) { + // A submodule in Index + // Nothing in Merge + // Something in Head // Submodules that disappear from the checkout must // be removed from the index, but not deleted from disk. remove(name); } else { + // Something different from a submodule in Index + // Nothing in Merge + // Something in Head if (equalIdAndMode(hId, hMode, iId, iMode)) { + // Index contains the same as Head + // Something different from a submodule in Index + // Nothing in Merge + // Something in Head if (f == null || f.isModified(dce, true)) + // file is dirty + // Index contains the same as Head + // Something different from a submodule in Index + // Nothing in Merge + // Something in Head + // -> file is dirty but is should be removed. That's + // a conflict conflict(name, dce, h, m); else + // file doesn't exist or is clean + // Index contains the same as Head + // Something different from a submodule in Index + // Nothing in Merge + // Something in Head + // -> Remove from index and delete the file remove(name); } else + // Index contains something different from Head + // Something different from a submodule in Index + // Nothing in Merge + // Something in Head + // -> Something new is in index (and maybe even on the + // filesystem). But Merge wants the path to be removed. + // Report a conflict conflict(name, dce, h, m); } } else { + // Something in Merge + // Something in Head + // Something in Index if (!equalIdAndMode(hId, hMode, mId, mMode) && !equalIdAndMode(hId, hMode, iId, iMode) && !equalIdAndMode(mId, mMode, iId, iMode)) + // All three contents in Head, Merge, Index differ from each + // other + // -> All contents differ. Report a conflict. conflict(name, dce, h, m); - else if (equalIdAndMode(hId, hMode, iId, iMode) + else + // At least two of the contents of Head, Index, Merge + // are the same + // Something in Merge + // Something in Head + // Something in Index + + if (equalIdAndMode(hId, hMode, iId, iMode) && !equalIdAndMode(mId, mMode, iId, iMode)) { + // Head contains the same as Index. Merge differs + // Something in Merge + // For submodules just update the index with the new SHA-1 if (dce != null && FileMode.GITLINK.equals(dce.getFileMode())) { + // Index and Head contain the same submodule. Merge + // differs + // Something in Merge + // -> Nothing new in index. Move to merge. + // Potentially updates the file + + // TODO check that we don't overwrite some unsaved + // file content update(name, mId, mMode); } else if (dce != null && (f == null || f.isModified(dce, true))) { + // File doesn't exist or is dirty + // Head and Index don't contain a submodule + // Head contains the same as Index. Merge differs + // Something in Merge + // -> Merge wants the index and file to be updated + // but the file is dirty. Report a conflict conflict(name, dce, h, m); } else { + // File exists and is clean + // Head and Index don't contain a submodule + // Head contains the same as Index. Merge differs + // Something in Merge + // -> Standard case when switching between branches: + // Nothing new in index but something different in + // Merge. Update index and file update(name, mId, mMode); } } else { + // Head differs from index or merge is same as index + // At least two of the contents of Head, Index, Merge + // are the same + // Something in Merge + // Something in Head + // Something in Index + + // Can be formulated as: Either all three states are + // equal or Merge is equal to Head or Index and differs + // to the other one. + // -> In all three cases we don't touch index and file. + keep(dce); } }