Merge pull request #17803 from paldepind/unreachable2

Rust: More test cases for rust/dead-code

rust/ql/test/query-tests/unusedentities/UnreachableCode.expected

@@ -1,14 +1,21 @@
-| unreachable.rs:12:3:12:17 | ExprStmt | This code is never reached. |
-| unreachable.rs:20:3:20:17 | ExprStmt | This code is never reached. |
-| unreachable.rs:32:3:32:17 | ExprStmt | This code is never reached. |
-| unreachable.rs:39:3:39:17 | ExprStmt | This code is never reached. |
-| unreachable.rs:60:2:60:16 | ExprStmt | This code is never reached. |
-| unreachable.rs:106:16:106:23 | ExprStmt | This code is never reached. |
-| unreachable.rs:114:15:114:22 | ExprStmt | This code is never reached. |
-| unreachable.rs:130:2:130:16 | ExprStmt | This code is never reached. |
-| unreachable.rs:140:2:140:16 | ExprStmt | This code is never reached. |
-| unreachable.rs:147:3:147:17 | ExprStmt | This code is never reached. |
-| unreachable.rs:156:4:156:18 | ExprStmt | This code is never reached. |
-| unreachable.rs:162:3:162:17 | ExprStmt | This code is never reached. |
-| unreachable.rs:168:4:168:18 | ExprStmt | This code is never reached. |
-| unreachable.rs:171:2:171:16 | ExprStmt | This code is never reached. |
+| unreachable.rs:13:3:13:17 | ExprStmt | This code is never reached. |
+| unreachable.rs:21:3:21:17 | ExprStmt | This code is never reached. |
+| unreachable.rs:33:3:33:17 | ExprStmt | This code is never reached. |
+| unreachable.rs:40:3:40:17 | ExprStmt | This code is never reached. |
+| unreachable.rs:61:2:61:16 | ExprStmt | This code is never reached. |
+| unreachable.rs:107:16:107:23 | ExprStmt | This code is never reached. |
+| unreachable.rs:115:15:115:22 | ExprStmt | This code is never reached. |
+| unreachable.rs:131:2:131:16 | ExprStmt | This code is never reached. |
+| unreachable.rs:141:2:141:16 | ExprStmt | This code is never reached. |
+| unreachable.rs:148:3:148:17 | ExprStmt | This code is never reached. |
+| unreachable.rs:157:4:157:18 | ExprStmt | This code is never reached. |
+| unreachable.rs:163:3:163:17 | ExprStmt | This code is never reached. |
+| unreachable.rs:169:4:169:18 | ExprStmt | This code is never reached. |
+| unreachable.rs:177:4:177:18 | ExprStmt | This code is never reached. |
+| unreachable.rs:180:2:180:16 | ExprStmt | This code is never reached. |
+| unreachable.rs:197:2:197:16 | ExprStmt | This code is never reached. |
+| unreachable.rs:203:3:203:17 | ExprStmt | This code is never reached. |
+| unreachable.rs:206:2:206:16 | ExprStmt | This code is never reached. |
+| unreachable.rs:218:3:218:17 | ExprStmt | This code is never reached. |
+| unreachable.rs:233:2:233:16 | ExprStmt | This code is never reached. |
+| unreachable.rs:242:2:242:16 | ExprStmt | This code is never reached. |

rust/ql/test/query-tests/unusedentities/UnusedValue.expected

@@ -28,3 +28,8 @@
 | more.rs:80:9:80:14 | a_ptr4 | Variable is assigned a value that is never used. |
 | more.rs:95:9:95:13 | d_ptr | Variable is assigned a value that is never used. |
 | more.rs:101:9:101:17 | f_ptr | Variable is assigned a value that is never used. |
+| unreachable.rs:166:6:166:6 | x | Variable is assigned a value that is never used. |
+| unreachable.rs:190:14:190:14 | a | Variable is assigned a value that is never used. |
+| unreachable.rs:199:9:199:9 | a | Variable is assigned a value that is never used. |
+| unreachable.rs:210:11:210:11 | a | Variable is assigned a value that is never used. |
+| unreachable.rs:217:6:217:6 | a | Variable is assigned a value that is never used. |

rust/ql/test/query-tests/unusedentities/main.rs

@@ -449,9 +449,14 @@ fn main() {
     func_ptrs();
     folds_and_closures();
 
-    unreachable_if();
+    unreachable_if_1();
     unreachable_panic();
     unreachable_match();
     unreachable_loop();
     unreachable_paren();
+    unreachable_let_1();
+    unreachable_let_2();
+    unreachable_if_2();
+    unreachable_if_3();
+
 }

rust/ql/test/query-tests/unusedentities/unreachable.rs

@@ -1,13 +1,14 @@
 
 //fn cond() -> bool;
 //fn get_a_number() -> i32;
+//fn maybe_get_a_number() -> Option<i32>;
 
 // --- unreachable code --
 
 fn do_something() {
 }
 
-fn unreachable_if() {
+fn unreachable_if_1() {
 	if false {
 		do_something(); // BAD: unreachable code
 	} else {
@@ -162,6 +163,14 @@ fn unreachable_loop() {
 		do_something(); // BAD: unreachable code
 	}
 
+	for x in 1..10 {
+		if cond() {
+			continue;
+			do_something(); // BAD: unreachable code
+		}
+		do_something();
+	}
+
 	loop {
 		if cond() {
 			return;
@@ -176,3 +185,59 @@ fn unreachable_loop() {
 fn unreachable_paren() {
 	let _ = (((1)));
 }
+
+fn unreachable_let_1() {
+	if let Some(a) = maybe_get_a_number() {
+		do_something();
+		return;
+	} else {
+		do_something();
+	}
+
+	do_something(); // SPURIOUS: unreachable code
+
+	if let a = get_a_number() { // (always succeeds)
+		do_something();
+		return;
+	} else {
+		do_something(); // BAD: unreachable code
+	}
+
+	do_something(); // BAD: unreachable code
+}
+
+fn unreachable_let_2() {
+	let Some(a) = maybe_get_a_number() else {
+		do_something();
+		return;
+	};
+
+	do_something();
+
+	let a = maybe_get_a_number() else { // (always succeeds)
+		do_something(); // BAD: unreachable code
+		return;
+	};
+
+	do_something();
+}
+
+fn unreachable_if_2() {
+	if cond() {
+		do_something();
+		return;
+	} else {
+		do_something();
+	}
+
+	do_something(); // SPURIOUS: unreachable code
+}
+
+fn unreachable_if_3() {
+	if !cond() {
+		do_something();
+		return;
+	}
+
+	do_something(); // SPURIOUS: unreachable code
+}