Merge pull request #218 from mvdan/error-checking

Error checking for doc generation

doc/cmd_test.go

@@ -11,7 +11,7 @@ import (
 )
 
 var flagb1, flagb2, flagb3, flagbr, flagbp bool
-var flags1, flags2a, flags2b, flags3, outs string
+var flags1, flags2a, flags2b, flags3 string
 var flagi1, flagi2, flagi3, flagir int
 
 const strtwoParentHelp = "help message for parent flag strtwo"

doc/man_docs.go

@@ -32,7 +32,7 @@ import (
 // correctly if your command names have - in them. If you have `cmd` with two
 // subcmds, `sub` and `sub-third`. And `sub` has a subcommand called `third`
 // it is undefined which help output will be in the file `cmd-sub-third.1`.
-func GenManTree(cmd *cobra.Command, header *GenManHeader, dir string) {
+func GenManTree(cmd *cobra.Command, header *GenManHeader, dir string) error {
 	if header == nil {
 		header = &GenManHeader{}
 	}
@@ -40,31 +40,28 @@ func GenManTree(cmd *cobra.Command, header *GenManHeader, dir string) {
 		if !c.IsAvailableCommand() || c.IsHelpCommand() {
 			continue
 		}
-		GenManTree(c, header, dir)
+		if err := GenManTree(c, header, dir); err != nil {
+			return err
+		}
 	}
-	out := new(bytes.Buffer)
-
 	needToResetTitle := header.Title == ""
 
-	GenMan(cmd, header, out)
+	filename := cmd.CommandPath()
+	filename = dir + strings.Replace(filename, " ", "-", -1) + ".1"
+	f, err := os.Create(filename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	if err := GenMan(cmd, header, f); err != nil {
+		return err
+	}
 
 	if needToResetTitle {
 		header.Title = ""
 	}
-
+	return nil
-	filename := cmd.CommandPath()
-	filename = dir + strings.Replace(filename, " ", "-", -1) + ".1"
-	outFile, err := os.Create(filename)
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	defer outFile.Close()
-	_, err = outFile.Write(out.Bytes())
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
 }
 
 // GenManHeader is a lot like the .TH header at the start of man pages. These
@@ -80,15 +77,16 @@ type GenManHeader struct {
 	Manual  string
 }
 
-// GenMan will generate a man page for the given command in the out buffer.
+// GenMan will generate a man page for the given command and write it to
-// The header argument may be nil, however obviously out may not.
+// w. The header argument may be nil, however obviously w may not.
-func GenMan(cmd *cobra.Command, header *GenManHeader, out io.Writer) {
+func GenMan(cmd *cobra.Command, header *GenManHeader, w io.Writer) error {
 	if header == nil {
 		header = &GenManHeader{}
 	}
-	buf := genMan(cmd, header)
+	b := genMan(cmd, header)
-	final := mangen.Render(buf)
+	final := mangen.Render(b)
-	out.Write(final)
+	_, err := w.Write(final)
+	return err
 }
 
 func fillHeader(header *GenManHeader, name string) {

doc/man_docs_test.go

@@ -29,7 +29,9 @@ func TestGenManDoc(t *testing.T) {
 		Section: "2",
 	}
 	// We generate on a subcommand so we have both subcommands and parents
-	GenMan(cmdEcho, header, out)
+	if err := GenMan(cmdEcho, header, out); err != nil {
+		t.Fatal(err)
+	}
 	found := out.String()
 
 	// Make sure parent has - in CommandPath() in SEE ALSO:
@@ -85,7 +87,9 @@ func TestGenManNoGenTag(t *testing.T) {
 		Section: "2",
 	}
 	// We generate on a subcommand so we have both subcommands and parents
-	GenMan(cmdEcho, header, out)
+	if err := GenMan(cmdEcho, header, out); err != nil {
+		t.Fatal(err)
+	}
 	found := out.String()
 
 	unexpected := translate("#HISTORY")

doc/md_docs.go

@@ -14,7 +14,6 @@
 package doc
 
 import (
-	"bytes"
 	"fmt"
 	"io"
 	"os"
@@ -25,29 +24,38 @@ import (
 	"github.com/spf13/cobra"
 )
 
-func printOptions(out io.Writer, cmd *cobra.Command, name string) {
+func printOptions(w io.Writer, cmd *cobra.Command, name string) error {
 	flags := cmd.NonInheritedFlags()
-	flags.SetOutput(out)
+	flags.SetOutput(w)
 	if flags.HasFlags() {
-		fmt.Fprintf(out, "### Options\n\n```\n")
+		if _, err := fmt.Fprintf(w, "### Options\n\n```\n"); err != nil {
+			return err
+		}
 		flags.PrintDefaults()
-		fmt.Fprintf(out, "```\n\n")
+		if _, err := fmt.Fprintf(w, "```\n\n"); err != nil {
+			return err
+		}
 	}
 
 	parentFlags := cmd.InheritedFlags()
-	parentFlags.SetOutput(out)
+	parentFlags.SetOutput(w)
 	if parentFlags.HasFlags() {
-		fmt.Fprintf(out, "### Options inherited from parent commands\n\n```\n")
+		if _, err := fmt.Fprintf(w, "### Options inherited from parent commands\n\n```\n"); err != nil {
-		parentFlags.PrintDefaults()
+			return err
-		fmt.Fprintf(out, "```\n\n")
 		}
+		parentFlags.PrintDefaults()
+		if _, err := fmt.Fprintf(w, "```\n\n"); err != nil {
+			return err
+		}
+	}
+	return nil
 }
 
-func GenMarkdown(cmd *cobra.Command, out io.Writer) {
+func GenMarkdown(cmd *cobra.Command, w io.Writer) error {
-	GenMarkdownCustom(cmd, out, func(s string) string { return s })
+	return GenMarkdownCustom(cmd, w, func(s string) string { return s })
 }
 
-func GenMarkdownCustom(cmd *cobra.Command, out io.Writer, linkHandler func(string) string) {
+func GenMarkdownCustom(cmd *cobra.Command, w io.Writer, linkHandler func(string) string) error {
 	name := cmd.CommandPath()
 
 	short := cmd.Short
@@ -56,29 +64,49 @@ func GenMarkdownCustom(cmd *cobra.Command, out io.Writer, linkHandler func(strin
 		long = short
 	}
 
-	fmt.Fprintf(out, "## %s\n\n", name)
+	if _, err := fmt.Fprintf(w, "## %s\n\n", name); err != nil {
-	fmt.Fprintf(out, "%s\n\n", short)
+		return err
-	fmt.Fprintf(out, "### Synopsis\n\n")
+	}
-	fmt.Fprintf(out, "\n%s\n\n", long)
+	if _, err := fmt.Fprintf(w, "%s\n\n", short); err != nil {
+		return err
+	}
+	if _, err := fmt.Fprintf(w, "### Synopsis\n\n"); err != nil {
+		return err
+	}
+	if _, err := fmt.Fprintf(w, "\n%s\n\n", long); err != nil {
+		return err
+	}
 
 	if cmd.Runnable() {
-		fmt.Fprintf(out, "```\n%s\n```\n\n", cmd.UseLine())
+		if _, err := fmt.Fprintf(w, "```\n%s\n```\n\n", cmd.UseLine()); err != nil {
+			return err
+		}
 	}
 
 	if len(cmd.Example) > 0 {
-		fmt.Fprintf(out, "### Examples\n\n")
+		if _, err := fmt.Fprintf(w, "### Examples\n\n"); err != nil {
-		fmt.Fprintf(out, "```\n%s\n```\n\n", cmd.Example)
+			return err
+		}
+		if _, err := fmt.Fprintf(w, "```\n%s\n```\n\n", cmd.Example); err != nil {
+			return err
+		}
 	}
 
-	printOptions(out, cmd, name)
+	if err := printOptions(w, cmd, name); err != nil {
+		return err
+	}
 	if hasSeeAlso(cmd) {
-		fmt.Fprintf(out, "### SEE ALSO\n")
+		if _, err := fmt.Fprintf(w, "### SEE ALSO\n"); err != nil {
+			return err
+		}
 		if cmd.HasParent() {
 			parent := cmd.Parent()
 			pname := parent.CommandPath()
 			link := pname + ".md"
 			link = strings.Replace(link, " ", "_", -1)
-			fmt.Fprintf(out, "* [%s](%s)\t - %s\n", pname, linkHandler(link), parent.Short)
+			if _, err := fmt.Fprintf(w, "* [%s](%s)\t - %s\n", pname, linkHandler(link), parent.Short); err != nil {
+				return err
+			}
 			cmd.VisitParents(func(c *cobra.Command) {
 				if c.DisableAutoGenTag {
 					cmd.DisableAutoGenTag = c.DisableAutoGenTag
@@ -96,48 +124,51 @@ func GenMarkdownCustom(cmd *cobra.Command, out io.Writer, linkHandler func(strin
 			cname := name + " " + child.Name()
 			link := cname + ".md"
 			link = strings.Replace(link, " ", "_", -1)
-			fmt.Fprintf(out, "* [%s](%s)\t - %s\n", cname, linkHandler(link), child.Short)
+			if _, err := fmt.Fprintf(w, "* [%s](%s)\t - %s\n", cname, linkHandler(link), child.Short); err != nil {
+				return err
+			}
+		}
+		if _, err := fmt.Fprintf(w, "\n"); err != nil {
+			return err
 		}
-		fmt.Fprintf(out, "\n")
 	}
 	if !cmd.DisableAutoGenTag {
-		fmt.Fprintf(out, "###### Auto generated by spf13/cobra on %s\n", time.Now().Format("2-Jan-2006"))
+		if _, err := fmt.Fprintf(w, "###### Auto generated by spf13/cobra on %s\n", time.Now().Format("2-Jan-2006")); err != nil {
+			return err
 		}
+	}
+	return nil
 }
 
-func GenMarkdownTree(cmd *cobra.Command, dir string) {
+func GenMarkdownTree(cmd *cobra.Command, dir string) error {
 	identity := func(s string) string { return s }
 	emptyStr := func(s string) string { return "" }
-	GenMarkdownTreeCustom(cmd, dir, emptyStr, identity)
+	return GenMarkdownTreeCustom(cmd, dir, emptyStr, identity)
 }
 
-func GenMarkdownTreeCustom(cmd *cobra.Command, dir string, filePrepender func(string) string, linkHandler func(string) string) {
+func GenMarkdownTreeCustom(cmd *cobra.Command, dir string, filePrepender, linkHandler func(string) string) error {
 	for _, c := range cmd.Commands() {
 		if !c.IsAvailableCommand() || c.IsHelpCommand() {
 			continue
 		}
-		GenMarkdownTreeCustom(c, dir, filePrepender, linkHandler)
+		if err := GenMarkdownTreeCustom(c, dir, filePrepender, linkHandler); err != nil {
+			return err
+		}
 	}
-	out := new(bytes.Buffer)
-
-	GenMarkdownCustom(cmd, out, linkHandler)
 
 	filename := cmd.CommandPath()
 	filename = dir + strings.Replace(filename, " ", "_", -1) + ".md"
-	outFile, err := os.Create(filename)
+	f, err := os.Create(filename)
 	if err != nil {
-		fmt.Println(err)
+		return err
-		os.Exit(1)
 	}
-	defer outFile.Close()
+	defer f.Close()
-	_, err = outFile.WriteString(filePrepender(filename))
+
-	if err != nil {
+	if _, err := io.WriteString(f, filePrepender(filename)); err != nil {
-		fmt.Println(err)
+		return err
-		os.Exit(1)
 	}
-	_, err = outFile.Write(out.Bytes())
+	if err := GenMarkdownCustom(cmd, f, linkHandler); err != nil {
-	if err != nil {
+		return err
-		fmt.Println(err)
-		os.Exit(1)
 	}
+	return nil
 }

doc/md_docs.md

@@ -39,13 +39,13 @@ This will write the markdown doc for ONLY "cmd" into the out, buffer.
 Both `GenMarkdown` and `GenMarkdownTree` have alternate versions with callbacks to get some control of the output:
 
 ```go
-func GenMarkdownTreeCustom(cmd *Command, dir string, filePrepender func(string) string, linkHandler func(string) string) {
+func GenMarkdownTreeCustom(cmd *Command, dir string, filePrepender, linkHandler func(string) string) error {
     //...
 }
 ```
 
 ```go
-func GenMarkdownCustom(cmd *Command, out *bytes.Buffer, linkHandler func(string) string) {
+func GenMarkdownCustom(cmd *Command, out *bytes.Buffer, linkHandler func(string) string) error {
     //...
 }
 ```

doc/md_docs_test.go

@@ -21,7 +21,9 @@ func TestGenMdDoc(t *testing.T) {
 	out := new(bytes.Buffer)
 
 	// We generate on s subcommand so we have both subcommands and parents
-	GenMarkdown(cmdEcho, out)
+	if err := GenMarkdown(cmdEcho, out); err != nil {
+		t.Fatal(err)
+	}
 	found := out.String()
 
 	// Our description
@@ -75,7 +77,9 @@ func TestGenMdNoTag(t *testing.T) {
 	cmdRootWithRun.PersistentFlags().StringVarP(&flags2a, "rootflag", "r", "two", strtwoParentHelp)
 	out := new(bytes.Buffer)
 
-	GenMarkdown(c, out)
+	if err := GenMarkdown(c, out); err != nil {
+		t.Fatal(err)
+	}
 	found := out.String()
 
 	unexpected := "Auto generated"