Support grouping dot and blank imports at the end (#88)

* feat: Support grouping dot and blank imports at the end

Signed-off-by: Marco Nenciarini <[email protected]>

* doc: Document blank and dot groups

Signed-off-by: Marco Nenciarini <[email protected]>

Author: mnencia

README.md

@@ -11,12 +11,15 @@ Name Path Comment
 ```
 All comments will keep as they were, except the independent comment blocks(line breaks before and after).
 
-GCI splits all import blocks into different sections, now support three section type:
+GCI splits all import blocks into different sections, now support five section type:
 - standard: Golang official imports, like "fmt"
-- custom: Custom section, use full and the longest match(match full string first, if multiple matches, use the longest one)
+- custom: Custom section, use full and the longest match (match full string first, if multiple matches, use the longest one)
 - default: All rest import blocks
+- blank: Put blank imports together in a separate group
+- dot: Put dot imports together in a separate group
 
-The priority is standard > default > custom, all sections sort alphabetically inside.
+The priority is standard > default > custom > blank > dot, all sections sort alphabetically inside.
+By default, blank and dot sections are not used and the corresponding lines end up in the other groups.
 
 All import blocks use one TAB(`\t`) as Indent.
 
@@ -50,11 +53,13 @@ Aliases:
 Flags:
   -d, --debug             Enables debug output from the formatter
   -h, --help              help for write
-  -s, --section strings   Sections define how inputs will be processed. Section names are case-insensitive and may contain parameters in (). The section order is standard > default > custom. The default value is [standard,default].
+  -s, --section strings   Sections define how inputs will be processed. Section names are case-insensitive and may contain parameters in (). The section order is standard > default > custom > blank > dot. The default value is [standard,default].
                           standard - standard section that Golang provides officially, like "fmt"
                           Prefix(github.com/daixiang0) - custom section, groups all imports with the specified Prefix. Imports will be matched to the longest Prefix.
-                          default - default section, contains all rest imports (default [standard,default])
+                          default - default section, contains all rest imports
+                          blank - blank section, contains all blank imports. This section is not presed unless explicitly enabled. (default [standard,default])
       --skip-generated    Skip generated files
+
 ```
 
 ```shell
@@ -70,11 +75,14 @@ Aliases:
 Flags:
   -d, --debug             Enables debug output from the formatter
   -h, --help              help for write
-  -s, --section strings   Sections define how inputs will be processed. Section names are case-insensitive and may contain parameters in (). The section order is standard > default > custom. The default value is [standard,default].
+  -s, --section strings   Sections define how inputs will be processed. Section names are case-insensitive and may contain parameters in (). The section order is standard > default > custom > blank > dot. The default value is [standard,default].
                           standard - standard section thatolang provides officially, like "fmt"
                           Prefix(github.com/daixiang0) - custom section, groups all imports with the specified Prefix. Imports will be matched to the longest Prefix.
-                          default - default section, contains all rest imports (default [standard,default])
+                          default - default section, contains all rest imports
+                          blank - blank section, contains all blank imports. This section is not presed unless explicitly enabled.
+                          dot - dot section, contains all dot imports. This section is not presed unless explicitly enabled. (default [standard,default])
       --skip-generated    Skip generated files
+
 ```
 
 ```shell
@@ -87,10 +95,12 @@ Usage:
 Flags:
   -d, --debug             Enables debug output from the formatter
   -h, --help              help for write
-  -s, --section strings   Sections define how inputs will be processed. Section names are case-insensitive and may contain parameters in (). The section order is standard > default > custom. The default value is [standard,default].
+  -s, --section strings   Sections define how inputs will be processed. Section names are case-insensitive and may contain parameters in (). The section order is standard > default > custom > blank > dot. The default value is [standard,default].
                           standard - standard section thatolang provides officially, like "fmt"
                           Prefix(github.com/daixiang0) - custom section, groups all imports with the specified Prefix. Imports will be matched to the longest Prefix.
-                          default - default section, contains all rest imports (default [standard,default])
+                          default - default section, contains all rest imports
+                          blank - blank section, contains all blank imports. This section is not presed unless explicitly enabled.
+                          dot - dot section, contains all dot imports. This section is not presed unless explicitly enabled. (default [standard,default])
       --skip-generated    Skip generated files
 
 ```
@@ -168,6 +178,40 @@ import (
 )
 ```
 
+### with blank and dot grouping enabled
+
+```go
+package main
+import (
+  "fmt"
+  go "github.com/golang"
+  _ "github.com/golang/blank"
+  . "github.com/golang/dot"
+  "github.com/daixiang0/gci"
+  _ "github.com/daixiang0/gci/blank"
+  . "github.com/daixiang0/gci/dot"
+)
+```
+
+to
+
+```go
+package main
+import (
+  "fmt"
+
+  go "github.com/golang"
+
+  "github.com/daixiang0/gci"
+
+  _ "github.com/daixiang0/gci/blank"
+  _ "github.com/golang/blank"
+
+  . "github.com/daixiang0/gci/dot"
+  . "github.com/golang/dot"
+)
+```
+
 ## TODO
 
 - Ensure only one blank between `Name` and `Path` in an import block

cmd/gci/gcicommand.go

@@ -46,10 +46,12 @@ func (e *Executor) newGciCommand(use, short, long string, aliases []string, stdI
 
 	debug = cmd.Flags().BoolP("debug", "d", false, "Enables debug output from the formatter")
 
-	sectionHelp := `Sections define how inputs will be processed. Section names are case-insensitive and may contain parameters in (). The section order is standard > default > custom. The default value is [standard,default].
+	sectionHelp := `Sections define how inputs will be processed. Section names are case-insensitive and may contain parameters in (). The section order is standard > default > custom > blank > dot. The default value is [standard,default].
 standard - standard section that Golang provides officially, like "fmt"
 Prefix(github.com/daixiang0) - custom section, groups all imports with the specified Prefix. Imports will be matched to the longest Prefix.
-default - default section, contains all rest imports`
+default - default section, contains all rest imports
+blank - blank section, contains all blank imports. This section is not presed unless explicitly enabled.
+dot - dot section, contains all dot imports. This section is not presed unless explicitly enabled.`
 
 	skipGenerated = cmd.Flags().Bool("skip-generated", false, "Skip generated files")
 

pkg/gci/gci.go

@@ -144,10 +144,8 @@ func LoadFormatGoFile(file io.FileObj, cfg config.Config) (src, dist []byte, err
 	tail := src[tailStart:]
 
 	// sort for custom sections
-	allKeys := make([]string, 0, len(result))
 	customKeys := make([]string, 0, len(result))
 	for k := range result {
-		allKeys = append(allKeys, k)
 		if strings.HasPrefix(k, "prefix(") {
 			customKeys = append(customKeys, k)
 		}
@@ -162,9 +160,8 @@ func LoadFormatGoFile(file io.FileObj, cfg config.Config) (src, dist []byte, err
 			AddIndent(&body, &firstWithIndex)
 			body = append(body, src[d.Start:d.End]...)
 		}
-		if len(allKeys) > 1 {
-			body = append(body, utils.Linebreak)
-		}
+
+		body = append(body, utils.Linebreak)
 	}
 
 	if len(result["default"]) > 0 {
@@ -173,9 +170,7 @@ func LoadFormatGoFile(file io.FileObj, cfg config.Config) (src, dist []byte, err
 			body = append(body, src[d.Start:d.End]...)
 		}
 
-		if len(customKeys) > 0 {
-			body = append(body, utils.Linebreak)
-		}
+		body = append(body, utils.Linebreak)
 	}
 
 	if len(customKeys) > 0 {
@@ -189,13 +184,37 @@ func LoadFormatGoFile(file io.FileObj, cfg config.Config) (src, dist []byte, err
 				body = append(body, utils.Linebreak)
 			}
 		}
+
+		body = append(body, utils.Linebreak)
+	}
+
+	if len(result["blank"]) > 0 {
+		for _, d := range result["blank"] {
+			AddIndent(&body, &firstWithIndex)
+			body = append(body, src[d.Start:d.End]...)
+		}
+
+		body = append(body, utils.Linebreak)
+	}
+
+	if len(result["dot"]) > 0 {
+		for _, d := range result["dot"] {
+			AddIndent(&body, &firstWithIndex)
+			body = append(body, src[d.Start:d.End]...)
+		}
+
+		body = append(body, utils.Linebreak)
 	}
 
 	// remove breakline in the end
-	if body[len(body)-1] == utils.Linebreak && tail[0] == utils.Linebreak {
+	for body[len(body)-1] == utils.Linebreak {
 		body = body[:len(body)-1]
 	}
 
+	if tail[0] != utils.Linebreak {
+		body = append(body, utils.Linebreak)
+	}
+
 	var totalLen int
 	slices := [][]byte{head, body, tail}
 	for _, s := range slices {

pkg/gci/internal/testdata/dot-and-blank.cfg.yaml

@@ -0,0 +1,6 @@
+sections:
+  - Standard
+  - Default
+  - Prefix(github.com/daixiang0)
+  - Blank
+  - Dot

pkg/gci/internal/testdata/dot-and-blank.in.go

@@ -0,0 +1,14 @@
+package main
+import (
+	"fmt"
+
+	g "github.com/golang"
+	. "github.com/golang/dot"
+	_ "github.com/golang/blank"
+
+	"github.com/daixiang0/a"
+	"github.com/daixiang0/gci"
+	"github.com/daixiang0/gci/subtest"
+	. "github.com/daixiang0/gci/dot"
+	_ "github.com/daixiang0/gci/blank"
+)

pkg/gci/internal/testdata/dot-and-blank.out.go

@@ -0,0 +1,16 @@
+package main
+import (
+	"fmt"
+
+	g "github.com/golang"
+
+	"github.com/daixiang0/a"
+	"github.com/daixiang0/gci"
+	"github.com/daixiang0/gci/subtest"
+
+	_ "github.com/daixiang0/gci/blank"
+	_ "github.com/golang/blank"
+
+	. "github.com/daixiang0/gci/dot"
+	. "github.com/golang/dot"
+)

pkg/section/blank.go

@@ -0,0 +1,19 @@
+package section
+
+import (
+	"github.com/daixiang0/gci/pkg/parse"
+	"github.com/daixiang0/gci/pkg/specificity"
+)
+
+type Blank struct{}
+
+func (b Blank) MatchSpecificity(spec *parse.GciImports) specificity.MatchSpecificity {
+	if spec.Name == "_" {
+		return specificity.NameMatch{}
+	}
+	return specificity.MisMatch{}
+}
+
+func (b Blank) String() string {
+	return "blank"
+}

pkg/section/dot.go

@@ -0,0 +1,19 @@
+package section
+
+import (
+	"github.com/daixiang0/gci/pkg/parse"
+	"github.com/daixiang0/gci/pkg/specificity"
+)
+
+type Dot struct{}
+
+func (d Dot) MatchSpecificity(spec *parse.GciImports) specificity.MatchSpecificity {
+	if spec.Name == "." {
+		return specificity.NameMatch{}
+	}
+	return specificity.MisMatch{}
+}
+
+func (d Dot) String() string {
+	return "dot"
+}

pkg/section/parser.go

@@ -29,6 +29,10 @@ func Parse(data []string) (SectionList, error) {
 			list = append(list, Custom{d[7 : len(d)-1]})
 		} else if strings.HasPrefix(s, "commentline(") && len(d) > 13 {
 			list = append(list, Custom{d[12 : len(d)-1]})
+		} else if s == "dot" {
+			list = append(list, Dot{})
+		} else if s == "blank" {
+			list = append(list, Blank{})
 		} else {
 			errString += fmt.Sprintf(" %s", s)
 		}

pkg/section/standard_list.go

@@ -0,0 +1,19 @@
+package specificity
+
+type NameMatch struct{}
+
+func (n NameMatch) IsMoreSpecific(than MatchSpecificity) bool {
+	return isMoreSpecific(n, than)
+}
+
+func (n NameMatch) Equal(to MatchSpecificity) bool {
+	return equalSpecificity(n, to)
+}
+
+func (n NameMatch) class() specificityClass {
+	return NameClass
+}
+
+func (n NameMatch) String() string {
+	return "Name"
+}

pkg/specificity/name.go

@@ -7,6 +7,7 @@ const (
 	DefaultClass  = 10
 	StandardClass = 20
 	MatchClass    = 30
+	NameClass     = 40
 )
 
 // MatchSpecificity is used to determine which section matches an import best