Merge lp:~chipaca/snappy/dynamicExclusion into lp:~snappy-dev/snappy/snappy-moved-to-github

[John Lenton]

Introducing .snapignore, which is made of lines of regexps and not globs.

[Zygmunt Krynicki (zyga)]

11:58 < zyga> Chipaca: one more suggestiong
11:58 < zyga> *on
11:58 < zyga> Chipaca: perhaps remove the built-in list and create the .snapingore file with that list if missing
11:58 < zyga> Chipaca: it's better than having two, one secred that nobody knows of, and one in the file
11:59 < Chipaca> hmm
11:59 < Chipaca> i see your point
12:00 < Chipaca> can you make that comment on the merge?
12:00 < Chipaca> i think it needs sergio or mvo to comment
12:00 < zyga> sure

[Sergio Schvezov (sergiusens)]

looks good, just a couple of comments

review: Needs Fixing

[Sergio Schvezov (sergiusens)]

> 11:58 < zyga> Chipaca: one more suggestiong
> 11:58 < zyga> *on
> 11:58 < zyga> Chipaca: perhaps remove the built-in list and create the
> .snapingore file with that list if missing
> 11:58 < zyga> Chipaca: it's better than having two, one secred that nobody
> knows of, and one in the file
> 11:59 < Chipaca> hmm
> 11:59 < Chipaca> i see your point
> 12:00 < Chipaca> can you make that comment on the merge?
> 12:00 < Chipaca> i think it needs sergio or mvo to comment
> 12:00 < zyga> sure

Only if explicit, maybe something like

snappy build --skeleton (which doesn't really assemble the package) but inserts a:
.snapignore # base
meta/.. # template

[lp:~chipaca/snappy/dynamicExclusion]

618. By John Lenton on 2015-07-29

addressed issues found in review

[John Lenton (chipaca)]

ok, in a different branch then.

[Sergio Schvezov (sergiusens)]

review: Approve

=== modified file 'snappy/build.go'
--- snappy/build.go	2015-07-23 11:05:37 +0000
+++ snappy/build.go	2015-07-29 13:13:40 +0000
@@ -51,7 +51,7 @@
 //
 // Please resist the temptation of optimizing the regexp by grouping
 // things by hand. People will find it unreadable enough as it is.
-var shouldExclude = regexp.MustCompile(strings.Join([]string{
+var shouldExcludeDefault = regexp.MustCompile(strings.Join([]string{
 	`\.snap$`, // added
 	`\.click$`,
 	`^\..*\.sw.$`,
@@ -82,8 +82,61 @@
 	`^_MTN$`,
 	`^_darcs$`,
 	`^{arch}$`,
+	`^\.snapignore$`,
 }, "|")).MatchString
 
+// fake static function variables
+type keep struct {
+	basedir string
+	exclude func(string) bool
+}
+
+func (k *keep) shouldExclude(basedir string, file string) bool {
+	if basedir == k.basedir {
+		if k.exclude == nil {
+			return false
+		}
+
+		return k.exclude(file)
+	}
+
+	k.basedir = basedir
+	k.exclude = nil
+
+	snapignore, err := os.Open(filepath.Join(basedir, ".snapignore"))
+	if err != nil {
+		return false
+	}
+
+	scanner := bufio.NewScanner(snapignore)
+	var lines []string
+	for scanner.Scan() {
+		line := scanner.Text()
+		if _, err := regexp.Compile(line); err != nil {
+			// not a regexp
+			line = regexp.QuoteMeta(line)
+		}
+		lines = append(lines, line)
+	}
+
+	fullRegex := strings.Join(lines, "|")
+	exclude, err := regexp.Compile(fullRegex)
+	if err == nil {
+		k.exclude = exclude.MatchString
+
+		return k.exclude(file)
+	}
+
+	// can't happen; can't even find a way to trigger it in testing.
+	panic(fmt.Sprintf("|-composition of valid regexps is invalid?!? Please report this bug: %#v", fullRegex))
+}
+
+var shouldExcludeDynamic = new(keep).shouldExclude
+
+func shouldExclude(basedir string, file string) bool {
+	return shouldExcludeDefault(file) || shouldExcludeDynamic(basedir, file)
+}
+
 // small helper that return the architecture or "multi" if its multiple arches
 func debArchitecture(m *packageYaml) string {
 	switch len(m.Architectures) {
@@ -375,7 +428,7 @@
 			return errin
 		}
 
-		if shouldExclude(filepath.Base(path)) {
+		if shouldExclude(sourceDir, filepath.Base(path)) {
 			if info.IsDir() {
 				return filepath.SkipDir
 			}

=== modified file 'snappy/build_test.go'
--- snappy/build_test.go	2015-06-08 16:26:25 +0000
+++ snappy/build_test.go	2015-07-29 13:13:40 +0000
@@ -356,6 +356,28 @@
 	c.Check(string(out), Matches, `(?m)Only in \S+: \.bzr`)
 }
 
+func (s *SnapTestSuite) TestExcludeDynamicFalseIfNoSnapignore(c *C) {
+	basedir := c.MkDir()
+	c.Check(shouldExcludeDynamic(basedir, "foo"), Equals, false)
+}
+
+func (s *SnapTestSuite) TestExcludeDynamicWorksIfSnapignore(c *C) {
+	basedir := c.MkDir()
+	c.Assert(ioutil.WriteFile(filepath.Join(basedir, ".snapignore"), []byte("foo\nb.r\n"), 0644), IsNil)
+	c.Check(shouldExcludeDynamic(basedir, "foo"), Equals, true)
+	c.Check(shouldExcludeDynamic(basedir, "bar"), Equals, true)
+	c.Check(shouldExcludeDynamic(basedir, "bzr"), Equals, true)
+	c.Check(shouldExcludeDynamic(basedir, "baz"), Equals, false)
+}
+
+func (s *SnapTestSuite) TestExcludeDynamicWeirdRegexps(c *C) {
+	basedir := c.MkDir()
+	c.Assert(ioutil.WriteFile(filepath.Join(basedir, ".snapignore"), []byte("*hello\n"), 0644), IsNil)
+	// note “*hello” is not a valid regexp, so will be taken literally (not globbed!)
+	c.Check(shouldExcludeDynamic(basedir, "ahello"), Equals, false)
+	c.Check(shouldExcludeDynamic(basedir, "*hello"), Equals, true)
+}
+
 func (s *SnapTestSuite) TestBuildSimpleOutputDir(c *C) {
 	sourceDir := makeExampleSnapSourceDir(c, `name: hello
 version: 1.0.1