Throws an error when `bat` is being user as pager.

As mentioned on #1334 `bat` should not be used as a value for `pager`,
this change checks both the balue of `bat` provided as a parameter or
as an environment variable.

3 files changed, 16 insertions, 2 deletions

diff --git a/src/error.rs b/src/error.rs
index 2e73b85b..3e5b3711 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -20,6 +20,10 @@ error_chain! {
             description("unknown syntax"),
             display("unknown syntax: '{}'", name)
         }
+        InvalidPagerValueBat {
+            description("invalid value `bat` for pager property"),
+            display("Use of bat as a pager is disallowed in order to avoid infinite recursion problems")
+        }
     }
 }
 
diff --git a/src/output.rs b/src/output.rs
index b0d5974e..689371b9 100644
--- a/src/output.rs
+++ b/src/output.rs
@@ -85,10 +85,10 @@ impl OutputType {
 
         match pagerflags.split_first() {
             Some((pager_name, args)) => {
-                let mut pager_path = PathBuf::from(pager_name);
+                let pager_path = PathBuf::from(pager_name);
 
                 if pager_path.file_stem() == Some(&OsString::from("bat")) {
-                    pager_path = PathBuf::from("less");
+                    return Err(ErrorKind::InvalidPagerValueBat.into());
                 }
 
                 let is_less = pager_path.file_stem() == Some(&OsString::from("less"));
diff --git a/tests/integration_tests.rs b/tests/integration_tests.rs
index da0690ef..09ac8498 100644
--- a/tests/integration_tests.rs
+++ b/tests/integration_tests.rs
@@ -406,6 +406,16 @@ fn pager_disable() {
 }
 
 #[test]
+fn pager_value_bat() {
+    bat()
+        .arg("--pager=bat")
+        .arg("--paging=always")
+        .arg("test.txt")
+        .assert()
+        .failure();
+}
+
+#[test]
 fn alias_pager_disable() {
     bat()
         .env("PAGER", "echo other-pager")