Implement --force_polling

README.md

@@ -146,13 +146,13 @@ Muzukashii:
   - [x] Directory watch
 - [ ] Commands
   - [x] `build`
-    - [x] `--source`, `--destination`, `--drafts`, `--future`, `--unpublished`, `--watch`
+    - [x] `--source`, `--destination`, `--drafts`, `--future`, `--unpublished`, `--watch`, `--force_polling`
     - [ ] `--baseurl`, `--config`, `--incremental`, `--lsi`
-    - [ ] `--force_polling`, `--limit-posts`, `JEKYLL_ENV=production` – not planned
+    - [ ] `--limit-posts`, `JEKYLL_ENV=production` – not planned
   - [x] `clean`
   - [x] `help`
   - [x] `serve`
-    - [x] `--open-uri`, `--host`, `--port`, `–watch` (enabled by default)
+    - [x] `--open-uri`, `--host`, `--port`, `–watch`, `--force_polling`
     - [ ] `--baseurl`, `--config`, `--incremental`
     - [ ] `--detach`, `--ssl`-* – not planned
   - [ ] `doctor`, `import`, `new`, `new-theme` – not planned

commands/flags.go

@@ -47,7 +47,8 @@ func init() {
 	app.HelpFlag.Short('h')
 	app.Flag("profile", "Create a Go pprof CPU profile").BoolVar(&profile)
 	app.Flag("quiet", "Silence (some) output.").Short('q').BoolVar(&quiet)
-	app.Flag("verbose", "Print verbose output.").Short('V').BoolVar(&options.Verbose)
+	_ = app.Flag("verbose", "Print verbose output.").Short('V').Action(boolVar("verbose", &options.Verbose)).Bool()
+	app.Flag("force_polling", "Force watch to use polling").BoolVar(&options.ForcePolling)
 	build.Flag("dry-run", "Dry run").Short('n').BoolVar(&options.DryRun)
 
 	// --watch has different defaults for build and serve

commands/run.go

@@ -23,7 +23,8 @@ func ParseAndRun(args []string) error {
 		options.Destination = &dest
 	}
 	if options.DryRun {
-		options.Verbose = true
+		verbose := true
+		options.Verbose = &verbose
 	}
 	return run(cmd)
 }

config/config.go

@@ -36,6 +36,9 @@ type Config struct {
 	// Plugins
 	ExcerptSeparator string `yaml:"excerpt_separator"`
 
+	// Conversion
+	Incremental bool
+
 	// Serving
 	Host        string
 	Port        int
@@ -44,12 +47,14 @@ type Config struct {
 
 	// Outputting
 	Permalink string
-	Timezone string
+	Timezone  string
+
+	Verbose bool
 
 	// CLI-only
-	DryRun  bool `yaml:"-"`
-	Verbose bool `yaml:"-"`
-	Watch   bool `yaml:"-"`
+	DryRun       bool `yaml:"-"`
+	ForcePolling bool `yaml:"-"`
+	Watch        bool `yaml:"-"`
 
 	Defaults []struct {
 		Scope struct {

config/default.go

@@ -46,6 +46,7 @@ plugins:   []
 
 # Conversion
 excerpt_separator: "\n\n"
+incremental: false
 
 # Serving
 detach:  false
@@ -57,4 +58,6 @@ baseurl: "" # does not include hostname
 permalink:     date
 paginate_path: /page:num
 timezone:      null
+
+verbose:  false
 `

config/flags.go

@@ -9,11 +9,11 @@ import (
 type Flags struct {
 	// these are pointers so we can tell whether they've been set, and override
 	// the config file only if
-	Destination, Host           *string
-	Drafts, Future, Unpublished *bool
-	Port                        *int
+	Destination, Host                    *string
+	Drafts, Future, Unpublished, Verbose *bool
+	Port                                 *int
 	// these aren't in the config file, so they can be treated more conventionally
-	DryRun, Verbose, Watch bool
+	DryRun, ForcePolling, Watch bool
 }
 
 // ApplyFlags overwrites the configuration with values from flags.

site/read.go

@@ -1,7 +1,6 @@
 package site
 
 import (
-	"fmt"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -54,7 +53,6 @@ func (s *Site) Read() error {
 // Reloaded returns a new site read the same source directory, configuration file, and load flags.
 func (s *Site) Reloaded(paths []string) (*Site, error) {
 	if s.requiresFullReload(paths) {
-		fmt.Println("reload everything")
 		copy, err := FromDirectory(s.SourceDir(), s.flags)
 		if err != nil {
 			return nil, err

site/watch.go

@@ -2,12 +2,15 @@ package site
 
 import (
 	"fmt"
+	"log"
 	"os"
+	"path/filepath"
 	"sync"
 	"time"
 
 	"github.com/fsnotify/fsnotify"
 	"github.com/osteele/gojekyll/utils"
+	"github.com/radovskyb/watcher"
 )
 
 // FilesEvent is a list of changed or added site source files, with a single
@@ -23,31 +26,9 @@ func (e FilesEvent) String() string {
 	return fmt.Sprintf("%d file%s changed at %s", count, inflect, e.Time.Format("3:04:05PM"))
 }
 
-func (s *Site) makeEventWatcher() (<-chan string, error) {
-	var (
-		sourceDir = s.SourceDir()
-		filenames = make(chan string, 100)
-		w, err    = fsnotify.NewWatcher()
-	)
-	if err != nil {
-		return nil, err
-	}
-	go func() {
-		for {
-			select {
-			case event := <-w.Events:
-				filenames <- utils.MustRel(sourceDir, event.Name)
-			case err := <-w.Errors:
-				fmt.Fprintln(os.Stderr, "error:", err)
-			}
-		}
-	}()
-	return filenames, w.Add(sourceDir)
-}
-
 // WatchFiles sends FilesEvent on changes within the site directory.
 func (s *Site) WatchFiles() (<-chan FilesEvent, error) {
-	filenames, err := s.makeEventWatcher()
+	filenames, err := s.makeFileWatcher()
 	if err != nil {
 		return nil, err
 	}
@@ -59,7 +40,7 @@ func (s *Site) WatchFiles() (<-chan FilesEvent, error) {
 		for {
 			paths := s.sitePaths(<-debounced)
 			if len(paths) > 0 {
-				// Make up a new timestamp. Except under pathological
+				// Create a new timestamp. Except under pathological
 				// circumstances, it will be close enough.
 				filesets <- FilesEvent{time.Now(), paths}
 			}
@@ -105,6 +86,72 @@ func (s *Site) WatchRebuild() (<-chan interface{}, error) {
 	return events, nil
 }
 
+func (s *Site) makePollingWatcher() (<-chan string, error) {
+	var (
+		sourceDir = utils.MustAbs(s.SourceDir())
+		filenames = make(chan string, 100)
+		w         = watcher.New()
+	)
+	if err := w.AddRecursive(sourceDir); err != nil {
+		return nil, err
+	}
+	for _, path := range s.config.Exclude {
+		if err := w.Ignore(filepath.Join(sourceDir, path)); err != nil {
+			return nil, err
+		}
+	}
+	if err := w.Ignore(s.DestDir()); err != nil {
+		return nil, err
+	}
+	go func() {
+		for {
+			select {
+			case event := <-w.Event:
+				filenames <- utils.MustRel(sourceDir, event.Path)
+			case err := <-w.Error:
+				fmt.Fprintln(os.Stderr, "error:", err)
+			case <-w.Closed:
+				return
+			}
+		}
+	}()
+	go func() {
+		if err := w.Start(time.Millisecond * 250); err != nil {
+			log.Fatal(err)
+		}
+	}()
+	return filenames, nil
+}
+
+func (s *Site) makeEventWatcher() (<-chan string, error) {
+	var (
+		sourceDir = s.SourceDir()
+		filenames = make(chan string, 100)
+		w, err    = fsnotify.NewWatcher()
+	)
+	if err != nil {
+		return nil, err
+	}
+	go func() {
+		for {
+			select {
+			case event := <-w.Events:
+				filenames <- utils.MustRel(sourceDir, event.Name)
+			case err := <-w.Errors:
+				fmt.Fprintln(os.Stderr, "error:", err)
+			}
+		}
+	}()
+	return filenames, w.Add(sourceDir)
+}
+
+func (s *Site) makeFileWatcher() (<-chan string, error) {
+	if s.config.ForcePolling {
+		return s.makePollingWatcher()
+	}
+	return s.makeEventWatcher()
+}
+
 // reloads and rebuilds the site; returns a copy and count
 func (s *Site) rebuild(paths []string) (r *Site, n int, err error) {
 	r, err = s.Reloaded(paths)
@@ -136,15 +183,18 @@ func (s *Site) sitePaths(filenames []string) []string {
 // faster than interval
 // TODO consider https://github.com/ReactiveX/RxGo
 func debounce(interval time.Duration, input <-chan string) <-chan []string {
-	output := make(chan []string)
 	var (
 		pending = []string{}
+		output  = make(chan []string)
 		ticker  <-chan time.Time
 	)
 	go func() {
 		for {
 			select {
 			case value := <-input:
+				if value == "." {
+					continue
+				}
 				pending = append(pending, value)
 				ticker = time.After(interval) // replaces the previous ticker
 			case <-ticker: