feat(spaced): Add spaced utility (#1)

.drone.yml

@@ -0,0 +1,56 @@
+kind: pipeline
+name: default
+
+platform:
+  os: linux
+  arch: amd64
+
+steps:
+  - name: lint + test
+    image: golang:1.11.2
+    commands:
+      - go get -u golang.org/x/lint/golint
+      - ./scripts/lint-test.sh
+    when:
+      event:
+        exclude:
+          - pull_request
+          - tag
+
+  - name: build + package
+    image: golang:1.11.2
+    commands:
+      - apt-get update && apt-get install --assume-yes zip
+      - ./scripts/build-package.sh
+    environment:
+      OUTDIR: /tmp/dist
+    volumes:
+      - name: dist
+        path: /tmp/dist
+    when:
+      event:
+        exclude:
+          - pull_request
+          - tag
+
+  - name: publish
+    image: node:10.14.0
+    commands:
+      - npx semantic-release
+    environment:
+      GITHUB_TOKEN:
+        from_secret: github/public_repo
+      # https://github.com/npm/uid-number/issues/7
+      NPM_CONFIG_UNSAFE_PERM: true
+    volumes:
+      - name: dist
+        path: /tmp/dist
+    when:
+      branch:
+        - master
+      event:
+        - push
+
+volumes:
+  - name: dist
+    temp: {}

.gitignore

@@ -1,4 +1,6 @@
+.temp/
 .vscode/
+dist/
 vendor/
 
 .DS_Store

.releaserc.yml

@@ -0,0 +1,16 @@
+repositoryUrl: [email protected]:72636c/hyperspaced
+branch: master
+
+ci: true
+debug: true
+
+plugins:
+  - '@semantic-release/commit-analyzer'
+  - '@semantic-release/release-notes-generator'
+  - - '@semantic-release/github'
+    - assets: '/tmp/dist/**'
+      failComment: false
+      failTitle: false
+      labels: false
+      releasedLabels: false
+      successComment: false

README.md

@@ -1 +1,54 @@
 # H Y P E R S P A C E D
+
+[![Build Status](https://cloud.drone.io/api/badges/72636c/hyperspaced/status.svg)](https://cloud.drone.io/72636c/hyperspaced)
+
+Command line utilities to improve the aesthetics of your favourite phrases with
+automatic space insertion (ASI).
+
+## Usage
+
+### CLI
+
+Prerequisites:
+
+- Go 1.11+
+
+```shell
+go install ./cmd/spaced
+```
+
+```shell
+echo 'gofmt urself' | spaced
+```
+
+### Go
+
+```go
+import (
+  "github.com/72636c/hyperspaced"
+)
+
+hyperspaced.Spaced("gofmt urself")
+```
+
+## Meta
+
+### CI/CD pipeline
+
+Builds and releases are automated with [Drone](https://drone.io/), which is
+impressively _"powered by blazing fast bare-metal servers"_, and more
+importantly _"written in Go"_.
+
+### Local scripts
+
+```shell
+./scripts/build-package.sh
+```
+
+```shell
+./scripts/lint-test.sh
+```
+
+### Mouseprint
+
+_This is a shameless rip-off of <https://www.npmjs.com/package/letter-spacing>._

cmd/spaced/main.go

@@ -0,0 +1,17 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/72636c/hyperspaced/internal/text"
+	"github.com/72636c/hyperspaced/internal/text/transform"
+)
+
+func main() {
+	err := text.LineFilter(transform.Spaced)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, "error: ", err)
+		os.Exit(1)
+	}
+}

go.mod

@@ -0,0 +1,3 @@
+module github.com/72636c/hyperspaced
+
+require golang.org/x/text v0.3.0

go.sum

@@ -0,0 +1,2 @@
+golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=

hyperspaced.go

@@ -0,0 +1,15 @@
+package hyperspaced
+
+import (
+	"github.com/72636c/hyperspaced/internal/text/transform"
+)
+
+// Spaced inserts a space between each character in a string.
+func Spaced(str string) string {
+	return transform.Spaced(str)
+}
+
+// SpacedN inserts n spaces between each character in a string.
+func SpacedN(str string, n int) string {
+	return transform.SpacedN(str, n)
+}

internal/text/char.go

@@ -0,0 +1,81 @@
+package text
+
+import (
+	"unicode"
+	"unicode/utf8"
+
+	"golang.org/x/text/unicode/norm"
+)
+
+// Char represents a character. Whatever that means.
+type Char []rune
+
+func (char Char) String() (str string) {
+	for _, r := range char {
+		str += string(r)
+	}
+
+	return
+}
+
+// SplitString splits a string into a slice of characters.
+//
+// It's obviously not perfect; don't @ me.
+func SplitString(str string) []Char {
+	var iter norm.Iter
+	iter.InitString(norm.NFC, str)
+
+	chars := make([]Char, 0)
+	runes := make([]rune, 0)
+
+	for !iter.Done() {
+		r, _ := utf8.DecodeRune(iter.Next())
+
+		if areSeparate(runes, r) {
+			chars = append(chars, Char(runes))
+			runes = []rune{r}
+		} else {
+			runes = append(runes, r)
+		}
+	}
+
+	if len(runes) == 0 {
+		return chars
+	}
+
+	return append(chars, Char(runes))
+}
+
+func areSeparate(runes []rune, next rune) bool {
+	if len(runes) == 0 {
+		return false
+	}
+
+	previous := runes[len(runes)-1]
+
+	return !isNull(previous) &&
+		!isJoinControl(previous) &&
+		!isJoinControl(next) &&
+		!isModifierSymbol(next) &&
+		!isVariationSelector(next)
+}
+
+// https://www.fileformat.info/info/unicode/char/0000/index.htm
+func isNull(r rune) bool {
+	return r == '\u0000'
+}
+
+// http://unicode.org/reports/tr44/#Join_Control
+func isJoinControl(r rune) bool {
+	return unicode.In(r, unicode.Join_Control)
+}
+
+// http://www.fileformat.info/info/unicode/category/Sk/list.htm
+func isModifierSymbol(r rune) bool {
+	return unicode.In(r, unicode.Sk)
+}
+
+// http://www.unicode.org/charts/PDF/UFE00.pdf
+func isVariationSelector(r rune) bool {
+	return unicode.In(r, unicode.Variation_Selector)
+}

internal/text/char_test.go

@@ -0,0 +1,75 @@
+package text_test
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/72636c/hyperspaced/internal/text"
+)
+
+func Test_SplitString(t *testing.T) {
+	testCases := []struct {
+		description string
+		input       string
+		expected    []text.Char
+	}{
+		{
+			description: "Empty String",
+			input:       "",
+			expected:    []text.Char{},
+		},
+		{
+			description: "One Letter",
+			input:       "f",
+			expected:    []text.Char{text.Char{'f'}},
+		},
+		{
+			description: "Two Letters",
+			input:       "hi",
+			expected:    []text.Char{text.Char{'h'}, text.Char{'i'}},
+		},
+		{
+			description: "Accent Normalisation",
+			input:       "e\u0301",
+			expected:    []text.Char{text.Char{'é'}},
+		},
+		{
+			description: "Separate Emoji",
+			input:       "\U0001f30f\u2696",
+			expected:    []text.Char{text.Char{'🌏'}, text.Char{'⚖'}},
+		},
+		{
+			// https://emojipedia.org/family-man-light-skin-tone-woman-light-skin-tone-girl-light-skin-tone-baby-light-skin-tone/
+			description: "Sequenced Emoji",
+			input:       "\U0001f468\U0001f3fb\u200d\U0001f469\U0001f3fb\u200d\U0001f467\U0001f3fb\u200d\U0001f476\U0001f3fb",
+			expected:    []text.Char{text.Char{'👨', '🏻', '\u200d', '👩', '🏻', '\u200d', '👧', '🏻', '\u200d', '👶', '🏻'}},
+		},
+		{
+			// https://emojipedia.org/female-sleuth/
+			description: "Female Variant Selector",
+			input:       "\U0001f575\ufe0f\u200d\u2640\ufe0f",
+			expected:    []text.Char{text.Char{'🕵', '\ufe0f', '\u200d', '♀', '\ufe0f'}},
+		},
+		{
+			// https://emojipedia.org/female-technologist/
+			description: "Join Control",
+			input:       "\U0001f469\u200d\U0001f4bb",
+			expected:    []text.Char{text.Char{'👩', '\u200d', '💻'}},
+		},
+		{
+			// https://emojipedia.org/man-type-6/
+			description: "Skin Tone Modifier",
+			input:       "\U0001f468\U0001f3ff",
+			expected:    []text.Char{text.Char{'👨', '🏿'}},
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.description, func(t *testing.T) {
+			actual := text.SplitString(testCase.input)
+			if !reflect.DeepEqual(actual, testCase.expected) {
+				t.Errorf("expected %+v, received %+v", testCase.expected, actual)
+			}
+		})
+	}
+}

internal/text/lineFilter.go

@@ -0,0 +1,26 @@
+package text
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+)
+
+// TransformLine is a function that transforms a line of text.
+type TransformLine func(string) string
+
+// LineFilter transforms lines of text as they pass from stdin to stdout.
+func LineFilter(transform TransformLine) error {
+	scanner := bufio.NewScanner(os.Stdin)
+
+	for scanner.Scan() {
+		output := transform(scanner.Text())
+
+		_, err := fmt.Println(output)
+		if err != nil {
+			return err
+		}
+	}
+
+	return scanner.Err()
+}