Читать книгу Practical Go - Amit Saha - Страница 40

//chap1/flag-parse/parse_args_test.go package main import ( "bytes" "errors" "testing" ) func TestParseArgs(t *testing.T) { tests := []struct { args []string err error numTimes int }{ { args: []string{"-h"}, err: errors.New("flag: help requested"), numTimes: 0, }, { args: []string{"-n", "10"}, err: nil, numTimes: 10, }, { args: []string{"-n", "abc"}, err: errors.New("invalid value \"abc\" for flag -n: parse error"), numTimes: 0, }, { args: []string{"-n", "1", "foo"}, err: errors.New("Positional arguments specified"), numTimes: 1, }, } byteBuf := new(bytes.Buffer) for _, tc := range tests { c, err := parseArgs(byteBuf, tc.args) if tc.result.err == nil && err != nil { t.Errorf("Expected nil error, got: %v\n", err) } if tc.result.err != nil && err.Error() != tc.result.err.Error() { t.Errorf("Expected error to be: %v, got: %v\n", tc.result.err, err) } if c.numTimes != tc.result.numTimes { t.Errorf("Expected numTimes to be: %v, got: %v\n", tc.result.numTimes, c.numTimes) } byteBuf.Reset() } }

Save Listing 1.6 into the directory in which you saved Listing 1.5. Name the file parse_args_test.go .

The unit test for the runCmd() function remains the same as that seen in Listing 1.4, except for the absence of the first test, which was used to test the behavior of runCmd() when printUsage was set to true. The test cases we want to test are as follows:

tests := []struct { c config input string output string err error }{ { c: config{numTimes: 5}, input: "", output: strings.Repeat("Your name please? Press the Enter key when done.\n", 1), err: errors.New("You didn't enter your name"), }, { c: config{numTimes: 5}, input: "Bill Bryson", output: "Your name please? Press the Enter key when done.\n" + strings.Repeat("Nice to meet you Bill Bryson\n", 5), }, }

You can find the complete test in the run_cmd_test.go file in the flag-parse subdirectory of the book's code.

The test for the validateArgs() function is the same as the one used in Listing 1.3. You can find it in the validate_args_test.go file in the flag-parse subdirectory of the book's code. Now, run all of the tests:

$ go test -v === RUN TestSetupFlagSet --- PASS: TestSetupFlagSet (0.00s) === RUN TestRunCmd --- PASS: TestRunCmd (0.00s) === RUN TestValidateArgs --- PASS: TestValidateArgs (0.00s) PASS ok github.com/practicalgo/code/chap1/flag-parse 0.610s

Great. Now you have rewritten the parsing logic of the greeter application to use the flag package and then updated the unit tests so that they test the new behavior. Next, you are going to work on improving the user interface of the application in a few ways. Before doing that, however, let's complete Exercise 1.2.

EXERCISE 1.2: HTML GREETER PAGE CREATOR In this exercise, you will update the greeter program to create an HTML page, which will serve as the home page for the user. Add a new option, -o , to the application, which will accept the filesystem path as a value. If the -o is specified, the greeter program will create an HTML page at the path specified with the following contents: <h1>Hello Jane Clancy</h1> , where Jane Clancy is the name entered. You may choose to use the html/template package for this exercise.