Adder: Disallow adding multiple directories unless "-w" is used.

Adding multiple directories without "-w" will not produce the expected
result, so for now it is best to disallow it.

This also added a NumFiles() method to SliceFile.

License: MIT
Signed-off-by: Kevin Atkinson <k@kevina.org>

commands/files/slicefile.go

@@ -23,6 +23,10 @@ func (f *SliceFile) IsDirectory() bool {
 	return true
 }
 
+func (f *SliceFile) NumFiles() int {
+	return len(f.files)
+}
+
 func (f *SliceFile) NextFile() (File, error) {
 	if f.n >= len(f.files) {
 		return nil, io.EOF

core/commands/add.go

@@ -80,6 +80,16 @@ You can now refer to the added file in a gateway, like so:
 		cmds.BoolOption(pinOptionName, "Pin this object when adding.").Default(true),
 	},
 	PreRun: func(req cmds.Request) error {
+		wrap, _, _ := req.Option(wrapOptionName).Bool()
+		recursive, _, _ := req.Option(cmds.RecLong).Bool()
+		sliceFile, ok := req.Files().(*files.SliceFile)
+		if !ok {
+			return fmt.Errorf("type assertion failed: req.Files().(*files.SliceFile)")
+		}
+		if !wrap && recursive && sliceFile.NumFiles() > 1 {
+			return fmt.Errorf("adding multiple directories without '-w' unsupported")
+		}
+
 		if quiet, _, _ := req.Option(quietOptionName).Bool(); quiet {
 			return nil
 		}

test/sharness/t0046-multifile-add.sh

@@ -50,4 +50,13 @@ test_expect_success "check that both files are added" '
 	test_cmp cat-expected cat-actual
 '
 
+test_expect_success "adding multiple directories fails cleanly" '
+	test_must_fail ipfs add -q -r dirA dirB
+'
+
+test_expect_success "adding multiple directories with -w is okay" '
+	ipfs add -q -r -w dirA dirB > hashes &&
+	ipfs ls `tail -1 hashes` > ls-res
+'
+
 test_done