Add dolt reset HEAD~ (#1512)

This pr adds `dolt reset HEAD~`

go/cmd/dolt/commands/reset.go

@@ -101,7 +101,22 @@ func (cmd ResetCmd) Exec(ctx context.Context, commandStr string, args []string,
 
 			err = actions.ResetHard(ctx, dEnv, arg, workingRoot, stagedRoot, headRoot)
 		} else {
-			stagedRoot, err = actions.ResetSoft(ctx, dEnv.DbData(), apr, stagedRoot, headRoot)
+			// Check whether the input argument is a ref.
+			if apr.NArg() == 1 {
+				argToCheck := apr.Arg(0)
+
+				ok := actions.ValidateIsRef(ctx, argToCheck, dEnv.DoltDB, dEnv.RepoStateReader())
+
+				// This is a valid ref
+				if ok {
+					err = actions.ResetSoftToRef(ctx, dEnv.DbData(), apr.Arg(0))
+					return handleResetError(err, usage)
+				}
+			}
+
+			tables := apr.Args()
+
+			stagedRoot, err = actions.ResetSoft(ctx, dEnv.DbData(), tables, stagedRoot, headRoot)
 
 			if err != nil {
 				return handleResetError(err, usage)
@@ -171,7 +186,12 @@ func printNotStaged(ctx context.Context, dEnv *env.DoltEnv, staged *doltdb.RootV
 func handleResetError(err error, usage cli.UsagePrinter) int {
 	if actions.IsTblNotExist(err) {
 		tbls := actions.GetTablesForError(err)
-		bdr := errhand.BuildDError("Invalid Table(s):")
+
+		// In case the ref does not exist.
+		bdr := errhand.BuildDError("Invalid Ref or Table:")
+		if len(tbls) > 1 {
+			bdr = errhand.BuildDError("Invalid Table(s):")
+		}
 
 		for _, tbl := range tbls {
 			bdr.AddDetails("\t" + tbl)

go/libraries/doltcore/doltdb/commit_spec.go

@@ -87,7 +87,7 @@ type CommitSpec struct {
 // * remotes/origin/master~~
 // * refs/heads/my-feature-branch^2~
 //
-// Constructing a |CommitSpec| does not mean the sepcified branch or commit
+// Constructing a |CommitSpec| does not mean the specified branch or commit
 // exists. This carries a description of how to find the specified commit. See
 // |doltdb.Resolve| for resolving a |CommitSpec| to a |Commit|.
 func NewCommitSpec(cSpecStr string) (*CommitSpec, error) {

go/libraries/doltcore/env/actions/reset.go

@@ -175,8 +175,8 @@ func ResetSoftTables(ctx context.Context, dbData env.DbData, apr *argparser.ArgP
 	return stagedRoot, nil
 }
 
-func ResetSoft(ctx context.Context, dbData env.DbData, apr *argparser.ArgParseResults, stagedRoot, headRoot *doltdb.RootValue) (*doltdb.RootValue, error) {
-	tables, err := getUnionedTables(ctx, apr.Args(), stagedRoot, headRoot)
+func ResetSoft(ctx context.Context, dbData env.DbData, tables []string, stagedRoot, headRoot *doltdb.RootValue) (*doltdb.RootValue, error) {
+	tables, err := getUnionedTables(ctx, tables, stagedRoot, headRoot)
 
 	if err != nil {
 		return nil, err
@@ -211,6 +211,38 @@ func ResetSoft(ctx context.Context, dbData env.DbData, apr *argparser.ArgParseRe
 	return stagedRoot, nil
 }
 
+// ResetSoftToRef matches the `git reset --soft <REF>` pattern. It resets both staged and head to the previous ref
+// and leaves the working unset. The user can then choose to create a commit that contains all changes since the ref.
+func ResetSoftToRef(ctx context.Context, dbData env.DbData, cSpecStr string) error {
+	cs, err := doltdb.NewCommitSpec(cSpecStr)
+	if err != nil {
+		return err
+	}
+
+	newHead, err := dbData.Ddb.Resolve(ctx, cs, dbData.Rsr.CWBHeadRef())
+	if err != nil {
+		return err
+	}
+
+	foundRoot, err := newHead.GetRootValue()
+	if err != nil {
+		return err
+	}
+
+	// Changed the stage to old the root. Leave the working as is.
+	_, err = env.UpdateStagedRoot(ctx, dbData.Ddb, dbData.Rsw, foundRoot)
+	if err != nil {
+		return err
+	}
+
+	// Update the head to this commit
+	if err = dbData.Ddb.SetHeadToCommit(ctx, dbData.Rsr.CWBHeadRef(), newHead); err != nil {
+		return err
+	}
+
+	return err
+}
+
 func getUnionedTables(ctx context.Context, tables []string, stagedRoot, headRoot *doltdb.RootValue) ([]string, error) {
 	if len(tables) == 0 || (len(tables) == 1 && tables[0] == ".") {
 		var err error
@@ -258,3 +290,18 @@ func resetStaged(ctx context.Context, ddb *doltdb.DoltDB, rsw env.RepoStateWrite
 
 	return updatedRoot, env.UpdateStagedRootWithVErr(ddb, rsw, updatedRoot)
 }
+
+// ValidateIsRef validates whether the input parameter is a valid cString
+func ValidateIsRef(ctx context.Context, cSpecStr string, ddb *doltdb.DoltDB, rsr env.RepoStateReader) bool {
+	cs, err := doltdb.NewCommitSpec(cSpecStr)
+	if err != nil {
+		return false
+	}
+
+	_, err = ddb.Resolve(ctx, cs, rsr.CWBHeadRef())
+	if err != nil {
+		return false
+	}
+
+	return true
+}

go/libraries/doltcore/sqle/json/noms_json_value_test.go

@@ -205,6 +205,8 @@ func TestJSONStructuralSharing(t *testing.T) {
 
 		err = db.Flush(ctx)
 		require.NoError(t, err)
+		err = db.(datas.GarbageCollector).GC(ctx)
+		require.NoError(t, err)
 		after := ts.Len()
 
 		// flush creates a single chunk

integration-tests/bats/docs.bats

@@ -328,7 +328,7 @@ SQL
     dolt add .
     run dolt reset LICENSE.md invalid
     [ "$status" -eq 1 ]
-    [[ "$output" =~ "Invalid Table(s)" ]] || false
+    [[ "$output" =~ "Invalid Ref or Table" ]] || false
     [[ "$output" =~ "invalid" ]] || false
     run dolt status
     [ "$status" -eq 0 ]

integration-tests/bats/status.bats

@@ -204,4 +204,201 @@ SQL
 @test "status: dolt reset --hard with more than one additional arg throws an error " {
     run dolt reset --hard HEAD HEAD2
     [ "$status" -eq 1 ]
+}
+
+@test "status: dolt reset hard with ~ works" {
+    dolt sql -q "CREATE TABLE test (pk int PRIMARY KEY);"
+    dolt commit -am "cm1"
+
+    dolt sql -q "INSERT INTO test values (1);"
+    dolt commit -am "cm2"
+
+    dolt sql -q "INSERT INTO test VALUES (2);"
+    dolt commit -am "cm3"
+
+    # Do a hard reset back one commit and confirm the appropriate values.
+    run dolt reset --hard HEAD~1
+    [ "$status" -eq 0 ]
+
+    run dolt sql -q "SELECT sum(pk) FROM test;"
+    [ "$status" -eq 0 ]
+    [[ "$output" =~ "1" ]] || false
+
+    # Since this is a hard reset double check the status
+    run dolt status
+    [ "$status" -eq 0 ]
+    [[ "$output" =~ "On branch master" ]] || false
+    [[ "$output" =~ "nothing to commit, working tree clean" ]] || false
+
+    # Run again with ~2 this time
+    dolt sql -q "INSERT INTO test VALUES (2);"
+    dolt commit -am "cm3"
+
+    # Do a hard reset back two commits and confirm the appropriate values.
+    run dolt reset --hard HEAD~2
+    [ "$status" -eq 0 ]
+
+    run dolt sql -q "SELECT sum(pk) FROM test;"
+    [ "$status" -eq 0 ]
+    [[ "$output" =~ "NULL" ]] || false
+
+    # Since this is a hard reset double check the status
+    run dolt status
+    [ "$status" -eq 0 ]
+    [[ "$output" =~ "On branch master" ]] || false
+    [[ "$output" =~ "nothing to commit, working tree clean" ]] || false
+}
+
+@test "status: dolt reset soft with ~ works" {
+    dolt sql -q "CREATE TABLE test (pk int PRIMARY KEY);"
+    dolt commit -am "cm1"
+
+    dolt sql -q "INSERT INTO test values (1);"
+    dolt commit -am "cm2"
+
+    # Make a dirty change
+    dolt sql -q "INSERT INTO test values (2)"
+    run dolt reset HEAD~
+    [ "$status" -eq 0 ]
+
+    # Verify that the changes are still there
+    run dolt sql -q "SELECT sum(pk) FROM test;"
+    [ "$status" -eq 0 ]
+    [[ "$output" =~ "3" ]] || false
+
+    # Now verify that commit log has changes
+    run dolt sql -q "SELECT count(*) from dolt_log"
+    [[ "$output" =~ "2" ]] || false
+
+    run dolt reset HEAD~1
+    [ "$status" -eq 0 ]
+
+    # Verify that the changes are still there
+    run dolt sql -q "SELECT sum(pk) FROM test;"
+    [ "$status" -eq 0 ]
+    [[ "$output" =~ "3" ]] || false
+
+    run dolt status
+    [[ "$output" =~ "Untracked files:" ]] || false
+    [[ "$output" =~ "  (use \"dolt add <table|doc>\" to include in what will be committed)" ]] || false
+    [[ "$output" =~ "	new table:      test" ]] || false
+
+    # Now verify that commit log has changes
+    run dolt sql -q "SELECT count(*) from dolt_log"
+    [[ "$output" =~ "1" ]] || false
+}
+
+@test "status: dolt reset works with commit hash ref" {
+    dolt sql -q "CREATE TABLE tb1 (pk int PRIMARY KEY);"
+    dolt sql -q "INSERT INTO tb1 values (1);"
+    dolt commit -am "cm1"
+
+    cm1=$(get_head_commit)
+
+    dolt sql -q "CREATE TABLE tb2 (pk int PRIMARY KEY);"
+    dolt sql -q "INSERT INTO tb2 values (11);"
+    dolt commit -am "cm2"
+
+    cm2=$(get_head_commit)
+
+    dolt sql -q "CREATE TABLE tb3 (pk int PRIMARY KEY);"
+    dolt sql -q "INSERT INTO tb3 values (11);"
+    dolt commit -am "cm3"
+
+    cm3=$(get_head_commit)
+
+    # Try a soft reset to commit 3. Nothing should change
+    dolt reset $cm3
+    run dolt status
+    [ "$status" -eq 0 ]
+    [[ "$output" =~ "On branch master" ]] || false
+    [[ "$output" =~ "nothing to commit, working tree clean" ]] || false
+
+    # Do a soft reset to commit 2.
+    dolt reset $cm2
+    run dolt status
+    [ "$status" -eq 0 ]
+    [[ "$output" =~ "Untracked files:" ]] || false
+    [[ "$output" =~ "  (use \"dolt add <table|doc>\" to include in what will be committed)" ]] || false
+    [[ "$output" =~ "	new table:      tb3" ]] || false
+    ! [[ "$output" =~ "	new table:      tb2" ]] || false
+
+    run dolt sql -q "SELECT COUNT(*) FROM tb3"
+    [[ "$output" =~ "1" ]] || false
+
+    run dolt sql -q "SELECT COUNT(*) FROM dolt_log"
+    [[ "$output" =~ "3" ]] || false # includes init commit
+
+    dolt commit -am "commit 3"
+
+    # Do a soft reset to commit 1
+    dolt reset $cm1
+    run dolt status
+    [ "$status" -eq 0 ]
+    [[ "$output" =~ "Untracked files:" ]] || false
+    [[ "$output" =~ "  (use \"dolt add <table|doc>\" to include in what will be committed)" ]] || false
+    [[ "$output" =~ "	new table:      tb3" ]] || false
+    [[ "$output" =~ "	new table:      tb2" ]] || false
+    ! [[ "$output" =~ "	new table:      tb1" ]] || false
+
+    run dolt sql -q "SELECT COUNT(*) FROM dolt_log"
+    [[ "$output" =~ "2" ]] || false # includes init commit
+}
+
+@test "status: dolt reset works with branch ref" {
+    dolt sql -q "CREATE TABLE tbl(pk int);"
+    dolt sql -q "INSERT into tbl VALUES (1)"
+    dolt commit -am "cm1"
+
+    # create a new branch and make a change
+    dolt checkout -b test
+    dolt sql -q "INSERT INTO tbl VALUES (2),(3)"
+    dolt sql -q "CREATE TABLE tbl2(pk int);"
+    dolt commit -am "test cm1"
+
+    # go back to master and merge
+    dolt checkout master
+    dolt merge test
+    dolt sql -q "INSERT INTO tbl VALUES (4)"
+    dolt commit -am "cm2"
+
+    # execute the reset
+    dolt reset test
+    run dolt status
+
+    [ "$status" -eq 0 ]
+    [[ "$output" =~ "Changes not staged for commit:" ]] || false
+    [[ "$output" =~ "  (use \"dolt add <table>\" to update what will be committed)" ]] || false
+    [[ "$output" =~ "  (use \"dolt checkout <table>\" to discard changes in working directory)" ]] || false
+    [[ "$output" =~ "	modified:       tbl" ]] || false
+    ! [[ "$output" =~ "	new table:      tb2" ]] || false
+}
+
+@test "status: dolt reset ref properly manages staged changes as well" {
+    dolt sql -q "CREATE TABLE tbl(pk int);"
+    dolt sql -q "INSERT into tbl VALUES (1)"
+    dolt commit -am "cm1"
+
+    dolt sql -q "INSERT INTO tbl VALUES (2)"
+    dolt add .
+
+    dolt reset HEAD
+    run dolt status
+
+    [ "$status" -eq 0 ]
+    [[ "$output" =~ "Changes not staged for commit:" ]] || false
+    [[ "$output" =~ "  (use \"dolt add <table>\" to update what will be committed)" ]] || false
+    [[ "$output" =~ "  (use \"dolt checkout <table>\" to discard changes in working directory)" ]] || false
+    [[ "$output" =~ "	modified:       tbl" ]] || false
+}
+
+@test "status: dolt reset throws errors for unknown ref/table" {
+    run dolt reset test
+    [ "$status" -eq 1 ]
+    [[ "$output" =~ "Invalid Ref or Table" ]] || false
+    [[ "$output" =~ "test" ]] || false
+}
+
+get_head_commit() {
+    dolt log -n 1 | grep -m 1 commit | cut -c 8-
 }