tests: add some basic chmod tests

Makefile

@@ -127,6 +127,7 @@ TEST_PROGS  := \
 	base64 \
 	basename \
 	cat \
+	chmod \
 	cksum \
 	comm \
 	cp \

tests/chmod.rs

@@ -0,0 +1,88 @@
+#[macro_use]
+mod common;
+
+use std::os::unix::raw::mode_t;
+use std::os::unix::fs::PermissionsExt;
+use std::os::unix::fs::OpenOptionsExt;
+use common::util::*;
+
+static UTIL_NAME: &'static str = "chmod";
+static TEST_FILE: &'static str = "file";
+
+struct TestCase {
+    args: Vec<&'static str>,
+    before: mode_t,
+    after: mode_t
+}
+
+fn mkfile(file: &str, mode: mode_t) {
+    std::fs::OpenOptions::new().mode(mode).create(true).open(file).unwrap();
+    let mut perms = std::fs::metadata(file).unwrap().permissions();
+    perms.set_mode(mode);
+    std::fs::set_permissions(file, perms).unwrap();
+}
+
+fn run_tests(tests: Vec<TestCase>) {
+    for test in tests {
+        let (at, mut ucmd) = testing(UTIL_NAME);
+
+        mkfile(&at.plus_as_string(TEST_FILE), test.before);
+        let perms = at.metadata(TEST_FILE).permissions().mode();
+        if perms != test.before{
+            panic!(format!("{}: expected: {:o} got: {:o}", "setting permissions failed", test.after, perms));
+        }
+
+        for arg in test.args {
+            ucmd.arg(arg);
+        }
+        let r = ucmd.run();
+        if !r.success {
+            println!("{}", r.stderr);
+            panic!(format!("{:?}: failed", ucmd.raw));
+        }
+
+        let perms = at.metadata(TEST_FILE).permissions().mode();
+        if perms != test.after {
+            panic!(format!("{:?}: expected: {:o} got: {:o}", ucmd.raw, test.after, perms));
+        }
+    }
+}
+
+#[test]
+fn test_chmod_octal() {
+    let tests = vec!{
+        TestCase{args: vec!{"0700",  TEST_FILE}, before: 0o000, after: 0o700},
+        TestCase{args: vec!{"0070",  TEST_FILE}, before: 0o000, after: 0o070},
+        TestCase{args: vec!{"0007",  TEST_FILE}, before: 0o000, after: 0o007},
+        TestCase{args: vec!{"-0700", TEST_FILE}, before: 0o700, after: 0o000},
+        TestCase{args: vec!{"-0070", TEST_FILE}, before: 0o060, after: 0o000},
+        TestCase{args: vec!{"-0007", TEST_FILE}, before: 0o001, after: 0o000},
+        TestCase{args: vec!{"+0100", TEST_FILE}, before: 0o600, after: 0o700},
+        TestCase{args: vec!{"+0020", TEST_FILE}, before: 0o050, after: 0o070},
+        TestCase{args: vec!{"+0004", TEST_FILE}, before: 0o003, after: 0o007},
+    };
+    run_tests(tests);
+}
+
+#[test]
+fn test_chmod_ugoa() {
+    let tests = vec!{
+        TestCase{args: vec!{"u=rwx", TEST_FILE}, before: 0o000, after: 0o700},
+        TestCase{args: vec!{"g=rwx", TEST_FILE}, before: 0o000, after: 0o070},
+        TestCase{args: vec!{"o=rwx", TEST_FILE}, before: 0o000, after: 0o007},
+        TestCase{args: vec!{"a=rwx", TEST_FILE}, before: 0o000, after: 0o777},
+    };
+    run_tests(tests);
+}
+
+#[test]
+fn test_chmod_ugo_copy() {
+    let tests = vec!{
+        TestCase{args: vec!{"u=g", TEST_FILE}, before: 0o070, after: 0o770},
+        TestCase{args: vec!{"g=o", TEST_FILE}, before: 0o005, after: 0o055},
+        TestCase{args: vec!{"o=u", TEST_FILE}, before: 0o200, after: 0o202},
+        TestCase{args: vec!{"u-g", TEST_FILE}, before: 0o710, after: 0o610},
+        TestCase{args: vec!{"u+g", TEST_FILE}, before: 0o250, after: 0o750},
+    };
+    run_tests(tests);
+}