Incremental pt. 2

config/config.go

@@ -112,6 +112,11 @@ func (c *Config) IsConfigPath(rel string) bool {
 	return rel == "_config.yml"
 }
 
+// SassDir returns the relative path of the SASS directory.
+func (c *Config) SassDir() string {
+	return "_sass"
+}
+
 // SourceDir returns the source directory as an absolute path.
 func (c *Config) SourceDir() string {
 	return utils.MustAbs(c.Source)

pages/file.go

@@ -12,7 +12,7 @@ import (
 // file is embedded in StaticFile and page
 type file struct {
 	site        Site
-	filename    string // target os filepath
+	filename    string // target filepath
 	relpath     string // slash-separated path relative to site or container source
 	outputExt   string
 	permalink   string // cached permalink
@@ -20,15 +20,6 @@ type file struct {
 	frontMatter map[string]interface{}
 }
 
-func (f *file) String() string {
-	return fmt.Sprintf("%T{Path=%v, Permalink=%v}", f, f.relpath, f.permalink)
-}
-
-func (f *file) OutputExt() string  { return f.outputExt }
-func (f *file) Permalink() string  { return f.permalink }
-func (f *file) Published() bool    { return templates.VariableMap(f.frontMatter).Bool("published", true) }
-func (f *file) SourcePath() string { return f.filename }
-
 // NewFile creates a Page or StaticFile.
 //
 // filename is the absolute filename. relpath is the path relative to the site or collection directory.
@@ -57,3 +48,23 @@ func NewFile(s Site, filename string, relpath string, defaults map[string]interf
 	p := &StaticFile{fields}
 	return p, nil
 }
+
+func (f *file) String() string {
+	return fmt.Sprintf("%T{Path=%v, Permalink=%v}", f, f.relpath, f.permalink)
+}
+
+func (f *file) OutputExt() string  { return f.outputExt }
+func (f *file) Permalink() string  { return f.permalink }
+func (f *file) Published() bool    { return templates.VariableMap(f.frontMatter).Bool("published", true) }
+func (f *file) SourcePath() string { return f.filename }
+
+// const requiresReloadError = error.Error("requires reload")
+
+func (f *file) Reload() error {
+	info, err := os.Stat(f.filename)
+	if err != nil {
+		return err
+	}
+	f.fileModTime = info.ModTime()
+	return nil
+}

pages/interfaces.go

@@ -18,6 +18,8 @@ type Document interface {
 	Published() bool
 	Static() bool
 	Write(io.Writer) error
+
+	Reload() error
 }
 
 // Site is the interface that the site provides to a page.

pages/page.go

@@ -42,27 +42,49 @@ type page struct {
 func (p *page) Static() bool { return false }
 
 func makePage(filename string, f file) (*page, error) {
-	b, err := ioutil.ReadFile(filename)
+	raw, lineNo, err := readFrontMatter(&f)
 	if err != nil {
 		return nil, err
 	}
-	lineNo := 1
-	frontMatter, err := frontmatter.Read(&b, &lineNo)
-	if err != nil {
-		return nil, err
-	}
-	f.frontMatter = templates.MergeVariableMaps(f.frontMatter, frontMatter)
 	p := page{
 		file:      f,
 		firstLine: lineNo,
-		raw:       b,
+		raw:       raw,
 	}
-	if err = p.setPermalink(); err != nil {
+	if err := p.setPermalink(); err != nil {
 		return nil, err
 	}
 	return &p, nil
 }
 
+func (p *page) Reload() error {
+	if err := p.file.Reload(); err != nil {
+		return err
+	}
+	// FIXME use original defaults
+	raw, lineNo, err := readFrontMatter(&p.file)
+	if err != nil {
+		return err
+	}
+	p.firstLine = lineNo
+	p.raw = raw
+	return nil
+}
+
+func readFrontMatter(f *file) (b []byte, lineNo int, err error) {
+	b, err = ioutil.ReadFile(f.filename)
+	if err != nil {
+		return
+	}
+	lineNo = 1
+	frontMatter, err := frontmatter.Read(&b, &lineNo)
+	if err != nil {
+		return
+	}
+	f.frontMatter = templates.MergeVariableMaps(f.frontMatter, frontMatter)
+	return
+}
+
 func (p *page) FrontMatter() map[string]interface{} {
 	return p.frontMatter
 }

pages/static_file.go

@@ -5,7 +5,7 @@ import (
 	"os"
 )
 
-// StaticFile is a static file.
+// A StaticFile is a static file. (Lint made me say this.)
 type StaticFile struct {
 	file
 }

plugins/feed.go

@@ -65,6 +65,7 @@ func (d *feedDoc) SourcePath() string { return "" }
 func (d *feedDoc) OutputExt() string  { return ".xml" }
 func (d *feedDoc) Published() bool    { return true }
 func (d *feedDoc) Static() bool       { return false } // FIXME means different things to different callers
+func (d *feedDoc) Reload() error      { return nil }
 
 func (d *feedDoc) Content() []byte {
 	bindings := map[string]interface{}{"site": d.site}

plugins/redirect_from.go

@@ -104,6 +104,7 @@ func (d *redirectionDoc) SourcePath() string { return "" } // FIXME bad design
 func (d *redirectionDoc) OutputExt() string  { return ".html" }
 func (d *redirectionDoc) Published() bool    { return true }
 func (d *redirectionDoc) Static() bool       { return false } // FIXME means different things to different callers
+func (d *redirectionDoc) Reload() error      { return nil }
 
 func (d *redirectionDoc) Content() []byte {
 	buf := new(bytes.Buffer)

plugins/template_doc.go

@@ -18,6 +18,7 @@ func (d *templateDoc) SourcePath() string { return "" }
 func (d *templateDoc) OutputExt() string  { return path.Ext(d.path) }
 func (d *templateDoc) Published() bool    { return true }
 func (d *templateDoc) Static() bool       { return false } // FIXME means different things to different callers
+func (d *templateDoc) Reload() error      { return nil }
 
 func (d *templateDoc) Content() []byte {
 	bindings := map[string]interface{}{"site": d.site}

site/rebuild.go

@@ -5,6 +5,9 @@ import (
 	"os"
 	"strings"
 	"time"
+
+	"github.com/osteele/gojekyll/pages"
+	"github.com/osteele/gojekyll/utils"
 )
 
 // WatchRebuild watches the site directory. Each time a file changes, it
@@ -52,23 +55,47 @@ func (s *Site) processFilesEvent(fileset FilesEvent, messages chan<- interface{}
 		return s
 	}
 	elapsed := time.Since(start)
-	messages <- fmt.Sprintf("wrote %d files in %.2fs.\n", count, elapsed.Seconds())
+	inflect := map[bool]string{true: "", false: "s"}[count == 1]
+	messages <- fmt.Sprintf("wrote %d file%s in %.2fs.\n", count, inflect, elapsed.Seconds())
 	return r
 }
 
 // reloads and rebuilds the site; returns a copy and count
-func (s *Site) rebuild(paths []string) (*Site, int, error) {
+func (s *Site) rebuild(paths []string) (r *Site, n int, err error) {
 	if s.requiresFullReload(paths) {
-		r, err := s.Reloaded(paths)
+		r, err = s.Reloaded(paths)
 		if err != nil {
-			return nil, 0, err
+			return
 		}
-		n, err := r.Build()
-		return r, n, err
+		n, err = r.Build()
+		return
 	}
-	return s, 0, nil
+	r = s
+	pathSet := utils.StringSet(paths)
+	for _, d := range s.docs {
+		if s.invalidatesDoc(pathSet, d) {
+			err = d.Reload()
+			if err != nil {
+				return
+			}
+			err = s.WriteDoc(d)
+			if err != nil {
+				return
+			}
+			n++
+		}
+	}
+	return
 }
 
+// Return true if a source file requires a full reload / rebuild.
+//
+// This is always true outside of incremental mode, since even a
+// static asset can cause pages to change if they reference its
+// variables.
+//
+// This function works on relative paths. It does not work for theme
+// sources.
 func (s *Site) requiresFullReload(paths []string) bool {
 	for _, path := range paths {
 		switch {
@@ -78,6 +105,8 @@ func (s *Site) requiresFullReload(paths []string) bool {
 			return false
 		case !s.config.Incremental:
 			return true
+		case strings.HasPrefix(path, s.config.SassDir()):
+			return true
 		case strings.HasPrefix(path, s.config.DataDir):
 			return true
 		case strings.HasPrefix(path, s.config.LayoutsDir):
@@ -87,23 +116,32 @@ func (s *Site) requiresFullReload(paths []string) bool {
 	return false
 }
 
-// relativize and de-dup filenames, and filter to those that affect the build
-func (s *Site) affectsBuildFilter(filenames []string) []string {
+// De-dup relative paths, and filter to those that might affect the build.
+//
+// Site watch uses this to decide when to send events.
+func (s *Site) affectsBuildFilter(paths []string) []string {
 	var (
-		result = make([]string, 0, len(filenames))
+		result = make([]string, 0, len(paths))
 		seen   = map[string]bool{}
 	)
 loop:
-	for _, path := range filenames {
+	for _, path := range paths {
 		switch {
 		case s.config.IsConfigPath(path):
+			// break
 		case s.Exclude(path):
 			continue loop
 		case seen[path]:
 			continue loop
 		}
-		seen[path] = true
 		result = append(result, path)
+		seen[path] = true
 	}
 	return result
 }
+
+// returns true if changes to the site-relative paths invalidate doc
+func (s *Site) invalidatesDoc(paths map[string]bool, d pages.Document) bool {
+	rel := utils.MustRel(s.SourceDir(), d.SourcePath())
+	return paths[rel]
+}

site/watch.go

@@ -49,10 +49,12 @@ func (s *Site) WatchFiles() (<-chan FilesEvent, error) {
 }
 
 func (s *Site) makeFileWatcher() (<-chan string, error) {
-	if s.config.ForcePolling {
+	switch {
+	case s.config.ForcePolling:
 		return s.makePollingWatcher()
+	default:
+		return s.makeEventWatcher()
 	}
-	return s.makeEventWatcher()
 }
 
 func (s *Site) makePollingWatcher() (<-chan string, error) {

utils/arrays.go

@@ -12,3 +12,12 @@ func SearchStrings(array []string, s string) bool {
 	}
 	return false
 }
+
+// StringSet creates a characteristic function map that tests for presence in an array.
+func StringSet(array []string) map[string]bool {
+	set := map[string]bool{}
+	for _, s := range array {
+		set[s] = true
+	}
+	return set
+}