tests/test-diff-ignore-whitespace

Prevent type exception on concatenation if diffstat returns None.

This will most often occur if diffstat is not installed in the
target platform, though may also happen in other cases where
diffstat fails to execute.

Signed-off-by: Sean Dague <[e-mail]>

#!/bin/sh

# GNU diff is the reference for all of these results.

hgdiff() {
    hg diff --nodates "$@"
}

test_added_blank_lines() {
    printf '\nhello world\n\ngoodbye world\n\n' >foo

    echo '>>> two diffs showing three added lines <<<'
    hgdiff
    hgdiff -b

    echo '>>> no diffs <<<'
    hgdiff -B
    hgdiff -Bb
}

test_added_horizontal_space_first_on_a_line() {
    printf '\t hello world\ngoodbye world\n' >foo

    echo '>>> four diffs showing added space first on the first line <<<'
    hgdiff
    hgdiff -b
    hgdiff -B
    hgdiff -Bb
}

test_added_horizontal_space_last_on_a_line() {
    printf 'hello world\t \ngoodbye world\n' >foo

    echo '>>> two diffs showing space appended to the first line <<<'
    hgdiff
    hgdiff -B

    echo '>>> no diffs <<<'
    hgdiff -b
    hgdiff -Bb
}

test_added_horizontal_space_in_the_middle_of_a_word() {
    printf 'hello world\ngood bye world\n' >foo

    echo '>>> four diffs showing space inserted into "goodbye" <<<'
    hgdiff
    hgdiff -B
    hgdiff -b
    hgdiff -Bb
}

test_increased_horizontal_whitespace_amount() {
    printf 'hello world\ngoodbye\t\t  \tworld\n' >foo

    echo '>>> two diffs showing changed whitespace amount in the last line <<<'
    hgdiff
    hgdiff -B

    echo '>>> no diffs <<<'
    hgdiff -b
    hgdiff -Bb
}

test_added_blank_line_with_horizontal_whitespace() {
    printf 'hello world\n \t\ngoodbye world\n' >foo

    echo '>>> four diffs showing added blank line w/horizontal space <<<'
    hgdiff
    hgdiff -B
    hgdiff -b
    hgdiff -Bb
}

hg init
printf 'hello world\ngoodbye world\n' >foo
hg ci -Amfoo -ufoo -d '0 0'

test_added_blank_lines
test_added_horizontal_space_first_on_a_line
test_added_horizontal_space_last_on_a_line
test_added_horizontal_space_in_the_middle_of_a_word
test_increased_horizontal_whitespace_amount
test_added_blank_line_with_horizontal_whitespace