Improved usage description, added clipboard option

• Dgen now has a proper usage description.
• No longer dependent on github.com/pkg/errors.
• Updated README.
• Added more presets.
• Updated Makefile.
• General code improvements.

Gopkg.toml

@@ -25,10 +25,6 @@
 #   unused-packages = true
 
 
-[[constraint]]
-  name = "github.com/pkg/errors"
-  version = "0.8.0"
-
 [prune]
   go-tests = true
   unused-packages = true

Makefile

@@ -1,4 +1,4 @@
-### Variables:
+## ----- Variables -----
 PKG_NAME = $(shell basename "$$(pwd)")
 
 ## Source config
@@ -10,37 +10,67 @@ TEST_TIMEOUT = 20s
 COVER_OUT = coverage.out
 
 
-### Commands (targets):
+## ------ Commands (targets) -----
 ## Prevent targeting filenames...
-.PHONY: default run build install all all-bench check fmt test test-v \
-		test-race bench
+.PHONY: default run build install get update review review-race review-bench \
+		check fmt test test-v test-race bench
 
 ## Default target when no arguments are given to make (build and run program).
 default: build run
 
 ## Builds and runs the program (package must be main).
 run:
 	@if [ -f ".env.sh" ]; then \
-		printf 'Exporting environment variables by sourcing ".env.sh"... ' && \
-		. .env.sh && \
-		echo "done!"; \
-	fi; \
-	if [ -f "$(PKG_NAME)" ]; then \
-		echo 'Running "$(PKG_NAME)"...' && \
-		./$(PKG_NAME); \
-	else echo '[ERROR] Could not find program "$(PKG_NAME)".'; \
-	fi
+	   printf 'Exporting environment variables by sourcing ".env.sh"... '; \
+	   . .env.sh; \
+	   echo "done."; \
+	 fi
+	@if [ -f "$(PKG_NAME)" ]; then \
+	   echo 'Running "$(PKG_NAME)"...'; \
+	   ./$(PKG_NAME); \
+	 else echo '[ERROR] Could not find program "$(PKG_NAME)".'; \
+	 fi
 
 ## Builds the program specified by the main package.
 build:
 	@printf "Building... "
-	@go build
-	@printf "done!\n"
+	@GOBUILD_OUT="$$(go build 2>&1)"; \
+		if [ -n "$$GOBUILD_OUT" ]; then \
+		  echo "\n[ERROR] Failed to build program:"; \
+		  echo $$GOBUILD_OUT; \
+		else echo "done."; \
+		fi
 
 install:
 	@printf 'Installing with "go install"... '
-	@go install
-	@echo "done!"
+	@GOINSTALL_OUT="$$(go install 2>&1)"; \
+		if [ -n "$$GOBUILD_OUT" ]; then \
+		  echo "\n[ERROR] failed to install:"; \
+		  echo "$$GOINSTALL_OUT"; \
+		else echo "done."; \
+		fi
+
+
+## Installs package dependencies.
+get:
+	@printf 'Installing package dependencies with "go get"... '
+	@GOGET_OUT="$$(go get ./... 2>&1)"; \
+		if [ -n "$$GOGET_OUT" ]; then \
+		  echo "\n[ERROR] Failed to install package dependencies:"; \
+		  echo "$$GOGET_OUT"; \
+		else echo "done."; \
+		fi
+
+## Installs and updates package dependencies.
+update:
+	@printf 'Installing and updating package dependencies with "go get"... '
+	@GOGET_OUT="$$(go get -u 2>&1)"; \
+			if [ -n "$$GOGET_OUT" ]; then \
+		  echo "\n[ERROR] Failed to install package dependencies:"; \
+		  echo "$$GOGET_OUT"; \
+		else echo "done."; \
+		fi
+
 
 ## Formats, checks, and tests the code.
 review: fmt check test
@@ -49,35 +79,51 @@ review-race: fmt check test-race
 ## Like "review-race", but includes benchmarks.
 review-bench: fmt check test-race bench
 
+
 ## Checks for formatting, linting, and suspicious code.
 check:
 ## Check formatting...
-	@printf "Check format:"
-	@GOFMT_OUT="$(shell gofmt -l $(SRC_FILES))"; if [ -n "$$GOFMT_OUT" ]; then \
-		printf "\n> [WARN] Fix formatting issues in the following files with "; \
-		printf '"make fmt":\n$$GOFMT_OUT\n\n'; else printf " ...OK!\n"; fi
+	@printf "Check fmt...                 "
+	@GOFMT_OUT="$$(gofmt -l $(SRC_FILES) 2>&1)"; \
+		if [ -n "$$GOFMT_OUT" ]; then \
+		  echo '\n[WARN] Fix formatting issues in the following files with \
+"make fmt":'; \
+		  echo "$$GOFMT_OUT\n"; \
+		else echo "ok"; \
+		fi
 ## Lint files...
-	@printf "Check lint:"
-	@GOLINT_OUT="$(shell for PKG in "$(SRC_PKGS)"; do golint $$PKG; done)"; \
-		if [ -n "$$GOLINT_OUT" ]; then printf "\n" && \
-		for PKG in "$$GOLINT_OUT"; do printf "> $$PKG\n"; done; printf "\n"; \
-		else printf " ...OK!\n"; fi
+	@printf "Check lint...                "
+	@GOLINT_OUT="$(for PKG in "$(SRC_PKGS)"; do golint $$PKG 2>&1; done)"; \
+		if [ -n "$$GOLINT_OUT" ]; then \
+		  printf "\n"; \
+		  for PKG in "$$GOLINT_OUT"; do \
+		    echo "$$PKG"; \
+		  done; \
+		  printf "\n"; \
+		else echo "ok"; \
+		fi
 ## Check suspicious code...
-	@printf "Check vet:"
-	@GOVET_OUT="$(shell go vet 2>&1)"; if [ -n "$$GOVET_OUT" ]; \
-		then printf '\n> [WARN] Fix suspicious code from "go vet":\n'; \
-		printf "$$GOVET_OUT\n\n"; else printf " ...OK!\n"; fi
+	@printf "Check vet...                 "
+	@GOVET_OUT="$$(go vet 2>&1)"; \
+		if [ -n "$$GOVET_OUT" ]; then \
+		  echo '\n[WARN] Fix suspicious code from "go vet":'; \
+		  echo "$$GOVET_OUT\n"; \
+		else echo "ok"; \
+		fi
 
 ## Reformats code according to "gofmt".
 fmt:
-	@echo Formatting:
-	@GOFMT_OUT=$(shell gofmt -l -s -w $(SRC_FILES)); if [ -n "$$GOFMT_OUT" ]; \
-		then for FILE in "$$GOFMT_OUT"; do printf "> $$FILE\n"; done; \
-		else printf "> ...all files formmatted correctly!\n"; fi
+	@printf "Formatting source files...   "
+	@GOFMT_OUT="$$(gofmt -l -s -w $(SRC_FILES) 2>&1)"; \
+	 if [ -n "$$GOFMT_OUT" ]; \
+	 then printf "\n$$GOFMT_OUT\n"; \
+	 else echo "ok"; \
+     fi;
 
 ## Testing commands:
-GOTEST = go test ./... -coverprofile=$(COVER_OUT) -covermode=atomic \
-	-timeout=$(TEST_TIMEOUT)
+GOTEST = go test ./... -coverprofile=$(COVER_OUT) \
+		               -covermode=atomic \
+		               -timeout=$(TEST_TIMEOUT)
 test:
 	@echo "Testing:"
 	@$(GOTEST)
@@ -89,4 +135,4 @@ test-race:
 	@$(GOTEST) -race
 bench:
 	@echo "Benchmarking..."
-	@go test ./... -run=$^ -bench=. -benchmem
+	@go test ./... -run=^$ -bench=. -benchmem

README.md

@@ -28,6 +28,63 @@ For more advanced usage options, view the help prompt with:
 dgen --help
 ```
 
+### Presets
+
+`dgen` comes with several presets in order to make your life easier. Each preset
+represents the character limit on the associated messaging service:
+
+```bash
+dgen "👀 " fb
+# Output: 👀 👀 👀 👀 👀 👀 👀 👀 👀 (... x5000)
+```
+
+#### List of current `dgen` presets:
+
+| Name / ID | Value  | service            |
+| --------- | ------ | ------------------ |
+| fb        | 5000   | Facebook Messenger |
+| twitter   | 280    | Twitter            |
+| rpost     | 40,000 | Reddit (post)      |
+| rcomment  | 10,000 | Reddit (comment)   |
+| rmsg      | 10,000 | Reddit (message)   |
+
+## Performance
+
+`dgen` is one of the top-of-the-line string generators out there. `dgen v1.0.1`
+sports the following benchmark:
+
+- **Input:** "benchmark test text "
+- **Repetitions:** 1,000,000
+- **Duration:** 25.050 seconds
+- **Milliseconds / operation:** 0.025039
+- **Byte allocated / operation:** 21
+- **Allocations / operation:** 0
+
+## Integration
+
+`dgen` is a wrapper around an internal library, `throughput`, which contains
+the real repeating and buffering logic. To create a program that is able to
+use `dgen`'s string dumping algorithm, simply import `throughput`:
+
+```go
+import (
+  "github.com/steven-xie/dgen/throughput"
+  "os"
+)
+
+
+func main() {
+  const (
+    in      = "test string "
+    reps    = 5000
+    bufsize = 3000
+  )
+
+  // Dump "test string " 5000 times into os.Stdout.
+  throughput.Dump(in, reps, bufsize, os.Stdout)
+}
+```
+
 [godoc-img]: https://godoc.org/github.com/steven-xie/dgen?status.svg
 [godoc]: https://godoc.org/github.com/steven-xie/dgen
 [travis-img]: https://travis-ci.org/steven-xie/dgen.svg?branch=master

args.go

@@ -13,11 +13,12 @@ func parseArgs(args []string) (str string, reps int) {
 
 	if nargs == 0 {
 		// Quit if no arguments were received.
-		fmt.Printf("Warning: Did not receive any arguments!\n\n")
+		errln("Warning: Did not receive any arguments!\n")
 		showHelp()
 
 		os.Exit(2)
 	}
+
 	if nargs > 2 {
 		// Warn the user if more arguments were received than expected.
 		fmt.Printf("Warning: Received more than 2 arguments. Ignoring the " +

config.go

@@ -22,7 +22,10 @@ const (
 var (
 	// Presets is a map of string identifiers to repeat counts. Identifiers
 	// correspond to various messaging services.
-	Presets = map[string]uint{"fb": 5000}
+	Presets = map[string]uint{
+		"fb": 5000, "rpost": 40000, "rcomment": 10000, "rmsg": 10000,
+		"twitter": 280,
+	}
 )
 
 func parsePreset(id string) int {

flags.go

@@ -9,14 +9,20 @@ import (
 var (
 	// Opts are flag-enabled options for dgen.
 	Opts struct {
-		// Stats will show statistics at the end of the string dump.
 		Stats    bool `short:"s" long:"stats" description:"Show statistics after string dump."`
 		Preserve bool `short:"p" long:"preserve" description:"Preserve whitespacing; do not add terminating newlines."`
+		Copy     bool `short:"c" long:"copy" description:"Write dump to clipboard, rather than to standard output."`
 	}
 
-	fparser = flags.NewParser(&Opts, flags.Default)
+	fparser = makeParser()
 )
 
+func makeParser() (p *flags.Parser) {
+	p = flags.NewParser(&Opts, flags.Default)
+	p.Usage = "[OPTIONS] <string> [<repeat count> | <preset name>]"
+	return p
+}
+
 func showHelp() {
 	fparser.WriteHelp(os.Stdout)
 }
@@ -43,14 +49,12 @@ func parseFlags() (args []string) {
 				os.Exit(4)
 
 			default:
-				fmt.Fprintln(os.Stderr, "Encountered flag parsing error of type:",
-					flagerr.Type)
+				errln("Encountered flag parsing error of type:", flagerr.Type)
 				os.Exit(4)
 			}
 		}
 
-		fmt.Fprintln(os.Stderr, "Failed to parse given flags (unknown error type):",
-			err)
+		errln("Failed to parse given flags (unknown error type):", err)
 		os.Exit(5)
 	}
 	return args

main.go

@@ -3,33 +3,50 @@ package main
 import (
 	"fmt"
 	"github.com/steven-xie/dgen/throughput"
+	"github.com/steven-xie/glip"
+	"io"
 	"os"
 )
 
 func main() {
 	args := parseFlags()
 	str, reps := parseArgs(args)
 
-	n, err := throughput.Dump(str, reps, Bufsize, os.Stdout)
+	// Set up output device.
+	var out io.Writer = os.Stdout
+	if Opts.Copy {
+		board, err := glip.NewBoard()
+		if err != nil {
+			errln("Failed to open system clipboard:", err)
+			os.Exit(1)
+		}
+		out = board
+	}
+
+	n, err := throughput.Dump(str, reps, Bufsize, out)
 
-	hasnl := hasTrailingNewline(str)
-	// Ensure that if extra info is about to be produced, there are at least two
-	// newlines before that info is printed.
-	if err != nil || Opts.Stats {
-		if hasnl {
+	// If wrote to os.Sdout...
+	if !Opts.Copy {
+		hasnl := hasTrailingNewline(str)
+
+		// Ensure that if extra info is about to be produced, there are at least two
+		// newlines before that info is printed.
+		if err != nil || Opts.Stats {
+			if hasnl {
+				fmt.Print("\n")
+			} else {
+				fmt.Print("\n\n")
+			}
+		} else if !Opts.Preserve && !hasnl {
 			fmt.Print("\n")
-		} else {
-			fmt.Print("\n\n")
 		}
-	} else if !Opts.Preserve && !hasnl {
-		fmt.Print("\n")
 	}
 
 	if err != nil {
-		fmt.Fprintln(os.Stderr, "Encountered error while dumping source string:",
-			err)
+		errln("Encountered error while dumping source string:", err)
 		os.Exit(7)
 	}
+
 	if Opts.Stats {
 		fmt.Printf("Successfully printed %d bytes.\n", n)
 	}