fix(scripts): correct usage and help exit status (#143)

tests/x-gh-get-latest-version.bats

@@ -2,6 +2,6 @@
 
 @test "x-gh-get-latest-version help" {
   run bash local/bin/x-gh-get-latest-version --help
-  [ "$status" -eq 1 ]
+  [ "$status" -eq 0 ]
   [[ "$output" == "Usage: x-gh-get-latest-version"* ]]
 }

tests/x-localip.bats

@@ -5,3 +5,9 @@
   [ "$status" -eq 0 ]
   [[ "$output" == "x-localip version"* ]]
 }
+
+@test "x-localip help" {
+  run bash local/bin/x-localip --help
+  [ "$status" -eq 0 ]
+  [[ "$output" == "Usage:"* ]]
+}

tests/x-mkd.bats

@@ -6,3 +6,9 @@
   [ "$status" -eq 0 ]
   [ -d "$dir" ]
 }
+
+@test "x-mkd with no args shows usage" {
+  run bash local/bin/x-mkd
+  [ "$status" -eq 1 ]
+  [[ "$output" == "Usage:"* ]]
+}

tests/x-path.bats

@@ -20,3 +20,9 @@
   VERBOSE=1 source local/bin/x-path-remove "$BATS_TMPDIR/dir"
   [ "$PATH" = "/usr/bin" ]
 }
+
+@test "x-path-append skips missing directory" {
+  PATH="/usr/bin"
+  VERBOSE=1 source local/bin/x-path-append "$BATS_TMPDIR/no-such"
+  [ "$PATH" = "/usr/bin" ]
+}