Add tests against issue sharkdp#2731

tests/integration_tests.rs

@@ -1020,6 +1020,31 @@ fn enable_pager_if_pp_flag_comes_before_paging() {
         .stdout(predicate::eq("pager-output\n").normalize());
 }
 
+#[test]
+fn paging_partially_overrides_plain() {
+    bat()
+        .env("PAGER", "echo pager-output")
+        .arg("--decorations=always")
+        .arg("--plain")
+        .arg("--paging=never")
+        .arg("test.txt")
+        .assert()
+        .success()
+        .stdout(predicate::eq("hello world\n"));
+}
+
+#[test]
+fn simple_plain_does_not_override_paging() {
+    bat()
+        .env("PAGER", "echo pager-output")
+        .arg("--paging=always")
+        .arg("--plain")
+        .arg("test.txt")
+        .assert()
+        .success()
+        .stdout(predicate::eq("pager-output\n"));
+}
+
 #[test]
 fn pager_failed_to_parse() {
     bat()