diff --git a/src/liballoc/tests/cow_str.rs b/src/liballoc/tests/cow_str.rs
index aa87ee84b3e97..63939686ab7c2 100644
--- a/src/liballoc/tests/cow_str.rs
+++ b/src/liballoc/tests/cow_str.rs
@@ -148,4 +148,4 @@ fn check_cow_clone_from() {
     let c2: Cow<str> = Cow::Owned(s);
     c1.clone_from(&c2);
     assert!(c1.into_owned().capacity() >= 25);
-}
\ No newline at end of file
+}
diff --git a/src/libcore/tests/ops.rs b/src/libcore/tests/ops.rs
index b81b3878c9d6e..9d2fa1abff658 100644
--- a/src/libcore/tests/ops.rs
+++ b/src/libcore/tests/ops.rs
@@ -67,4 +67,4 @@ fn test_range_inclusive() {
     r = RangeInclusive { start: 1, end: -1 };
     assert_eq!(r.size_hint(), (0, Some(0)));
     assert_eq!(r.next(), None);
-}
\ No newline at end of file
+}
diff --git a/src/libserialize/collection_impls.rs b/src/libserialize/collection_impls.rs
index de7eebe7bf3fb..3a05cb7187d80 100644
--- a/src/libserialize/collection_impls.rs
+++ b/src/libserialize/collection_impls.rs
@@ -241,4 +241,4 @@ impl<T: Decodable> Decodable for Arc<[T]> {
             Ok(vec.into())
         })
     }
-}
\ No newline at end of file
+}
diff --git a/src/test/codegen/prefetch.rs b/src/test/codegen/prefetch.rs
index 9ca2f01f80d7d..3a23c16d5214d 100644
--- a/src/test/codegen/prefetch.rs
+++ b/src/test/codegen/prefetch.rs
@@ -71,5 +71,3 @@ pub fn check_prefetch_write_instruction(data: &[i8]) {
         prefetch_write_instruction(data.as_ptr(), 3);
     }
 }
-
-
diff --git a/src/test/compile-fail/E0004.rs b/src/test/compile-fail/E0004.rs
index 79e53c7a29fdb..8df07a0c1c5b2 100644
--- a/src/test/compile-fail/E0004.rs
+++ b/src/test/compile-fail/E0004.rs
@@ -19,4 +19,4 @@ fn main() {
     match x { //~ ERROR E0004
         Terminator::TalkToMyHand => {}
     }
-}
\ No newline at end of file
+}
diff --git a/src/test/compile-fail/duplicate_entry_error.rs b/src/test/compile-fail/duplicate_entry_error.rs
index ad5ea29159968..485519e8c3d7e 100644
--- a/src/test/compile-fail/duplicate_entry_error.rs
+++ b/src/test/compile-fail/duplicate_entry_error.rs
@@ -20,4 +20,4 @@ fn panic_fmt() -> ! {
     loop {}
 }
 
-fn main() {}
\ No newline at end of file
+fn main() {}
diff --git a/src/test/compile-fail/float-int-invalid-const-cast.rs b/src/test/compile-fail/float-int-invalid-const-cast.rs
index 2efefd926919f..1f07422e21be4 100644
--- a/src/test/compile-fail/float-int-invalid-const-cast.rs
+++ b/src/test/compile-fail/float-int-invalid-const-cast.rs
@@ -58,4 +58,4 @@ fn main() {
     { const X: u32 = 4294967296. as u32; force(X); } //~ ERROR constant evaluation error
     { const X: u128 = 1e40 as u128; force(X); } //~ ERROR constant evaluation error
     { const X: i128 = 1e40 as i128; force(X); } //~ ERROR constant evaluation error
-}
\ No newline at end of file
+}
diff --git a/src/test/compile-fail/issue-28848.rs b/src/test/compile-fail/issue-28848.rs
index 3d23ce0ee4e61..1a06d59f0b191 100644
--- a/src/test/compile-fail/issue-28848.rs
+++ b/src/test/compile-fail/issue-28848.rs
@@ -20,4 +20,4 @@ pub fn foo<'a, 'b>(u: &'b ()) -> &'a () {
     Foo::<'a, 'b>::xmute(u) //~ ERROR lifetime bound not satisfied
 }
 
-fn main() {}
\ No newline at end of file
+fn main() {}
diff --git a/src/test/compile-fail/never-assign-wrong-type.rs b/src/test/compile-fail/never-assign-wrong-type.rs
index d854e6eb20388..c0dd2cab749f4 100644
--- a/src/test/compile-fail/never-assign-wrong-type.rs
+++ b/src/test/compile-fail/never-assign-wrong-type.rs
@@ -16,5 +16,3 @@
 fn main() {
     let x: ! = "hello"; //~ ERROR mismatched types
 }
-
-
diff --git a/src/test/compile-fail/range_inclusive_gate.rs b/src/test/compile-fail/range_inclusive_gate.rs
index 69b9a4c67adc3..5b063dc1137c0 100644
--- a/src/test/compile-fail/range_inclusive_gate.rs
+++ b/src/test/compile-fail/range_inclusive_gate.rs
@@ -19,5 +19,3 @@ pub fn main() {
     //~| ERROR core_intrinsics
     //~| ERROR core_intrinsics
 }
-
-
diff --git a/src/test/compile-fail/useless_comment.rs b/src/test/compile-fail/useless_comment.rs
index a1172bb214d0a..90eb66728fce5 100644
--- a/src/test/compile-fail/useless_comment.rs
+++ b/src/test/compile-fail/useless_comment.rs
@@ -27,4 +27,4 @@ fn foo() {
 
 fn main() {
     foo();
-}
\ No newline at end of file
+}
diff --git a/src/test/incremental/hashes/enum_defs.rs b/src/test/incremental/hashes/enum_defs.rs
index 02746785856cc..36cbd2239a052 100644
--- a/src/test/incremental/hashes/enum_defs.rs
+++ b/src/test/incremental/hashes/enum_defs.rs
@@ -651,5 +651,3 @@ mod change_trait_bound_indirectly_where {
         Variant1(T)
     }
 }
-
-
diff --git a/src/test/incremental/hashes/inline_asm.rs b/src/test/incremental/hashes/inline_asm.rs
index b93a96566031c..3996e92e05a91 100644
--- a/src/test/incremental/hashes/inline_asm.rs
+++ b/src/test/incremental/hashes/inline_asm.rs
@@ -236,6 +236,3 @@ pub fn change_options(_a: i32) -> i32 {
     }
     _out
 }
-
-
-
diff --git a/src/test/mir-opt/return_an_array.rs b/src/test/mir-opt/return_an_array.rs
index 4409f16b3f5ff..bfae5b9438970 100644
--- a/src/test/mir-opt/return_an_array.rs
+++ b/src/test/mir-opt/return_an_array.rs
@@ -15,4 +15,4 @@ fn foo() -> [u8; 1024] {
         return x;
 }
 
-fn main() { }
\ No newline at end of file
+fn main() { }
diff --git a/src/test/parse-fail/issue-37113.rs b/src/test/parse-fail/issue-37113.rs
index caf451099d714..14c6f3944bb59 100644
--- a/src/test/parse-fail/issue-37113.rs
+++ b/src/test/parse-fail/issue-37113.rs
@@ -18,4 +18,4 @@ macro_rules! test_macro {
 
 fn main() {
     test_macro!(String,);
-}
\ No newline at end of file
+}
diff --git a/src/test/parse-fail/range_inclusive_gate.rs b/src/test/parse-fail/range_inclusive_gate.rs
index de690c3fea3cf..6b6afc504e150 100644
--- a/src/test/parse-fail/range_inclusive_gate.rs
+++ b/src/test/parse-fail/range_inclusive_gate.rs
@@ -72,5 +72,3 @@ pub fn main() {
     o!(); // not allowed in macros that output cfgs
     p!(); // not allowed in cfg'ed macros that output cfgs
 }
-
-
diff --git a/src/test/run-fail/return-never-coerce.rs b/src/test/run-fail/return-never-coerce.rs
index 4cd93ac7e1a5d..ddcecd97ba596 100644
--- a/src/test/run-fail/return-never-coerce.rs
+++ b/src/test/run-fail/return-never-coerce.rs
@@ -24,5 +24,3 @@ fn main() {
     let x: i32 = call_another_fn(wub);
     let y: u32 = wub();
 }
-
-
diff --git a/src/test/run-make/a-b-a-linker-guard/a.rs b/src/test/run-make/a-b-a-linker-guard/a.rs
index e6cbe2e64d0e9..c6680a78819db 100644
--- a/src/test/run-make/a-b-a-linker-guard/a.rs
+++ b/src/test/run-make/a-b-a-linker-guard/a.rs
@@ -16,5 +16,3 @@ pub fn foo(x: u32) { }
 
 #[cfg(y)]
 pub fn foo(x: i32) { }
-
-
diff --git a/src/test/run-make/reproducible-build/reproducible-build.rs b/src/test/run-make/reproducible-build/reproducible-build.rs
index dc7c702e5cc67..b47d780e52984 100644
--- a/src/test/run-make/reproducible-build/reproducible-build.rs
+++ b/src/test/run-make/reproducible-build/reproducible-build.rs
@@ -124,5 +124,3 @@ fn main() {
 
     TupleStruct(1, 2, 3, 4).bar();
 }
-
-
diff --git a/src/test/run-pass/abi-sysv64-register-usage.rs b/src/test/run-pass/abi-sysv64-register-usage.rs
index 1cae86712668b..e701329127502 100644
--- a/src/test/run-pass/abi-sysv64-register-usage.rs
+++ b/src/test/run-pass/abi-sysv64-register-usage.rs
@@ -102,4 +102,4 @@ pub fn main() {
 }
 
 #[cfg(not(target_arch = "x86_64"))]
-pub fn main() {}
\ No newline at end of file
+pub fn main() {}
diff --git a/src/test/run-pass/auxiliary/issue_42007_s.rs b/src/test/run-pass/auxiliary/issue_42007_s.rs
index b965e916f98f0..91ad9869ed856 100644
--- a/src/test/run-pass/auxiliary/issue_42007_s.rs
+++ b/src/test/run-pass/auxiliary/issue_42007_s.rs
@@ -11,4 +11,4 @@
 #[repr(u8)]
 pub enum E {
     B = 1 as u8,
-}
\ No newline at end of file
+}
diff --git a/src/test/run-pass/for-loop-mut-ref-element.rs b/src/test/run-pass/for-loop-mut-ref-element.rs
index 14ce23b07242c..556c846b0b8e1 100644
--- a/src/test/run-pass/for-loop-mut-ref-element.rs
+++ b/src/test/run-pass/for-loop-mut-ref-element.rs
@@ -12,4 +12,4 @@
 
 fn main() {
     for ref mut _a in std::iter::once(true) {}
-}
\ No newline at end of file
+}
diff --git a/src/test/run-pass/generator/borrow-in-tail-expr.rs b/src/test/run-pass/generator/borrow-in-tail-expr.rs
index df1a1dcebe606..486fe3c900d8b 100644
--- a/src/test/run-pass/generator/borrow-in-tail-expr.rs
+++ b/src/test/run-pass/generator/borrow-in-tail-expr.rs
@@ -16,4 +16,4 @@ fn main() {
         let a = String::new();
         a.len()
     };
-}
\ No newline at end of file
+}
diff --git a/src/test/run-pass/generator/match-bindings.rs b/src/test/run-pass/generator/match-bindings.rs
index 9c6b0571e58c5..231aa1b42f021 100644
--- a/src/test/run-pass/generator/match-bindings.rs
+++ b/src/test/run-pass/generator/match-bindings.rs
@@ -27,4 +27,4 @@ fn main() {
             yield;
         }
     };
-}
\ No newline at end of file
+}
diff --git a/src/test/run-pass/generator/yield-subtype.rs b/src/test/run-pass/generator/yield-subtype.rs
index 5ff070f311e01..5ea4b1fe93c80 100644
--- a/src/test/run-pass/generator/yield-subtype.rs
+++ b/src/test/run-pass/generator/yield-subtype.rs
@@ -20,4 +20,4 @@ fn bar<'a>() {
     };
 }
 
-fn main() {}
\ No newline at end of file
+fn main() {}
diff --git a/src/test/run-pass/issue-22066.rs b/src/test/run-pass/issue-22066.rs
index 2817ef77108b0..c2486f0dcb498 100644
--- a/src/test/run-pass/issue-22066.rs
+++ b/src/test/run-pass/issue-22066.rs
@@ -18,4 +18,4 @@ pub trait LineFormatter<'a> {
     }
 }
 
-fn main() {}
\ No newline at end of file
+fn main() {}
diff --git a/src/test/run-pass/issue-32292.rs b/src/test/run-pass/issue-32292.rs
index 3995caa32bf17..ed319b1391dc3 100644
--- a/src/test/run-pass/issue-32292.rs
+++ b/src/test/run-pass/issue-32292.rs
@@ -15,4 +15,4 @@ struct Foo;
 
 fn main() {
     let _ = Foo;
-}
\ No newline at end of file
+}
diff --git a/src/test/run-pass/issue-33992.rs b/src/test/run-pass/issue-33992.rs
index 5729469f69754..98da7d46b1aa3 100644
--- a/src/test/run-pass/issue-33992.rs
+++ b/src/test/run-pass/issue-33992.rs
@@ -37,4 +37,4 @@ pub static TEST7: bool = true;
 #[linkage = "weak_odr"]
 pub static TEST8: bool = true;
 
-fn main() {}
\ No newline at end of file
+fn main() {}
diff --git a/src/test/run-pass/issue-35376.rs b/src/test/run-pass/issue-35376.rs
index 25895cd0753e4..9e4eb84edc67c 100644
--- a/src/test/run-pass/issue-35376.rs
+++ b/src/test/run-pass/issue-35376.rs
@@ -48,4 +48,4 @@ pub struct Handle;
 
 impl Beta for Handle {
     type Event = ();
-}
\ No newline at end of file
+}
diff --git a/src/test/run-pass/optimization-fuel-1.rs b/src/test/run-pass/optimization-fuel-1.rs
index 5f294e26aa53e..e3529ebfb0d81 100644
--- a/src/test/run-pass/optimization-fuel-1.rs
+++ b/src/test/run-pass/optimization-fuel-1.rs
@@ -22,5 +22,3 @@ fn main() {
         +(size_of::<S2>() == 4) as usize;
     assert_eq!(optimized, 1);
 }
-
-
diff --git a/src/test/rustdoc/doc-cfg.rs b/src/test/rustdoc/doc-cfg.rs
index cfb37912fe757..8499e5c741ee0 100644
--- a/src/test/rustdoc/doc-cfg.rs
+++ b/src/test/rustdoc/doc-cfg.rs
@@ -44,4 +44,4 @@ pub mod unix_only {
     impl ArmOnly for super::Portable {
         fn unix_and_arm_only_function() {}
     }
-}
\ No newline at end of file
+}
diff --git a/src/test/ui-fulldeps/update-references.sh b/src/test/ui-fulldeps/update-references.sh
index b9ded7d1e951c..c2c842fcc4984 100644
--- a/src/test/ui-fulldeps/update-references.sh
+++ b/src/test/ui-fulldeps/update-references.sh
@@ -46,5 +46,3 @@ while [[ "$1" != "" ]]; do
         cp $BUILD_DIR/$STDERR_NAME $MYDIR/$STDERR_NAME
     fi
 done
-
-
diff --git a/src/test/ui/in-band-lifetimes/single_use_lifetimes-4.rs b/src/test/ui/in-band-lifetimes/single_use_lifetimes-4.rs
index ead987a09ab97..4ac8f8c0d4e22 100644
--- a/src/test/ui/in-band-lifetimes/single_use_lifetimes-4.rs
+++ b/src/test/ui/in-band-lifetimes/single_use_lifetimes-4.rs
@@ -17,4 +17,4 @@ enum Bar<'x> { //~ ERROR lifetime name `'x` only used once
     Variant(&'x u32)
 }
 
-fn main() { }
\ No newline at end of file
+fn main() { }
diff --git a/src/test/ui/in-band-lifetimes/single_use_lifetimes.rs b/src/test/ui/in-band-lifetimes/single_use_lifetimes.rs
index 96aaf8923f140..a97056b6240ec 100644
--- a/src/test/ui/in-band-lifetimes/single_use_lifetimes.rs
+++ b/src/test/ui/in-band-lifetimes/single_use_lifetimes.rs
@@ -13,4 +13,4 @@ fn deref<'x>(v: &'x u32) -> u32 { //~ ERROR lifetime name `'x` only used once
     *v
 }
 
-fn main() {}
\ No newline at end of file
+fn main() {}
diff --git a/src/test/ui/update-references.sh b/src/test/ui/update-references.sh
index b9ded7d1e951c..c2c842fcc4984 100755
--- a/src/test/ui/update-references.sh
+++ b/src/test/ui/update-references.sh
@@ -46,5 +46,3 @@ while [[ "$1" != "" ]]; do
         cp $BUILD_DIR/$STDERR_NAME $MYDIR/$STDERR_NAME
     fi
 done
-
-
diff --git a/src/tools/tidy/src/style.rs b/src/tools/tidy/src/style.rs
index 40d84b98d3a7d..b784a0e4c5fa0 100644
--- a/src/tools/tidy/src/style.rs
+++ b/src/tools/tidy/src/style.rs
@@ -130,6 +130,7 @@ pub fn check(path: &Path, bad: &mut bool) {
         let skip_tab = contents.contains("ignore-tidy-tab");
         let skip_length = contents.contains("ignore-tidy-linelength");
         let skip_end_whitespace = contents.contains("ignore-tidy-end-whitespace");
+        let mut trailing_new_lines = 0;
         for (i, line) in contents.split("\n").enumerate() {
             let mut err = |msg: &str| {
                 tidy_error!(bad, "{}:{}: {}", file.display(), i + 1, msg);
@@ -161,10 +162,20 @@ pub fn check(path: &Path, bad: &mut bool) {
             if filename.ends_with(".cpp") && line.contains("llvm_unreachable") {
                 err(LLVM_UNREACHABLE_INFO);
             }
+            if line.is_empty() {
+                trailing_new_lines += 1;
+            } else {
+                trailing_new_lines = 0;
+            }
         }
         if !licenseck(file, &contents) {
             tidy_error!(bad, "{}: incorrect license", file.display());
         }
+        match trailing_new_lines {
+            0 => tidy_error!(bad, "{}: missing trailing newline", file.display()),
+            1 | 2 => {}
+            n => tidy_error!(bad, "{}: too many trailing newlines ({})", file.display(), n),
+        };
     })
 }