Fix clippy warnings introduced in Rust 1.75 (#437)

src/cwe_checker_lib/src/abstract_domain/bricks.rs

@@ -165,15 +165,13 @@ impl BricksDomain {
 
         for i in 0..long_list.len() {
             if empty_bricks_added >= len_diff {
-                new_list.push(short_list.get(0).unwrap().clone());
+                new_list.push(short_list[0].clone());
                 short_list.remove(0);
-            } else if short_list.is_empty()
-                || short_list.get(0).unwrap() != long_list.get(i).unwrap()
-            {
+            } else if short_list.is_empty() || &short_list[0] != long_list.get(i).unwrap() {
                 new_list.push(BrickDomain::get_empty_brick_domain());
                 empty_bricks_added += 1;
             } else {
-                new_list.push(short_list.get(0).unwrap().clone());
+                new_list.push(short_list[0].clone());
                 short_list.remove(0);
             }
         }

src/cwe_checker_lib/src/analysis/function_signature/mod.rs

@@ -70,7 +70,7 @@ fn generate_fixpoint_computation<'a>(
     // Set the node values for all function entry nodes.
     for node in graph.node_indices() {
         if let Node::BlkStart(block, sub) = graph[node] {
-            if let Some(entry_block) = sub.term.blocks.get(0) {
+            if let Some(entry_block) = sub.term.blocks.first() {
                 if entry_block.tid == block.tid {
                     // The node of a function entry point
                     let calling_convention = project

src/cwe_checker_lib/src/analysis/graph.rs

@@ -512,7 +512,7 @@ pub fn get_entry_nodes_of_subs(graph: &Graph) -> HashMap<Tid, NodeIndex> {
     let mut sub_to_entry_node_map: HashMap<Tid, NodeIndex> = HashMap::new();
     for node in graph.node_indices() {
         if let Node::BlkStart(block, sub) = graph[node] {
-            if let Some(entry_block) = sub.term.blocks.get(0) {
+            if let Some(entry_block) = sub.term.blocks.first() {
                 if block.tid == entry_block.tid {
                     sub_to_entry_node_map.insert(sub.tid.clone(), node);
                 }

src/cwe_checker_lib/src/analysis/pointer_inference/mod.rs

@@ -305,7 +305,7 @@ impl<'a> PointerInference<'a> {
                     call: (caller_blk, _caller_sub),
                     return_: _,
                 } => {
-                    let call_tid = match caller_blk.term.jmps.get(0) {
+                    let call_tid = match caller_blk.term.jmps.first() {
                         Some(call) => &call.tid,
                         _ => continue,
                     };

src/cwe_checker_lib/src/analysis/stack_alignment_substitution/mod.rs

@@ -90,7 +90,7 @@ fn journal_sp_value(
 
 /// Returns the tid of the target of the first Jmp::Branch of the provided block.
 fn get_first_branch_tid(blk: &Term<Blk>) -> Option<&Tid> {
-    if let Some(jmp) = blk.term.jmps.get(0) {
+    if let Some(jmp) = blk.term.jmps.first() {
         if let Jmp::Branch(jump_to_blk) = &jmp.term {
             return Some(jump_to_blk);
         }

src/cwe_checker_lib/src/analysis/string_abstraction/context/mod.rs

@@ -74,7 +74,7 @@ impl<'a, T: AbstractDomain + HasTop + Eq + From<String> + DomainInsertion> Conte
         for (node_id, node) in pointer_inference_results.get_graph().node_references() {
             match node {
                 Node::BlkStart(block, sub) => {
-                    if let Some(def) = block.term.defs.get(0) {
+                    if let Some(def) = block.term.defs.first() {
                         block_start_node_map.insert((def.tid.clone(), sub.tid.clone()), node_id);
                         block_first_def_set.insert((def.tid.clone(), sub.tid.clone()));
                     }

src/cwe_checker_lib/src/analysis/string_abstraction/mod.rs

@@ -56,7 +56,7 @@ impl<'a, T: AbstractDomain + DomainInsertion + HasTop + Eq + From<String>>
 
         let mut sub_to_entry_blocks_map = HashMap::new();
         for sub in project.program.term.subs.values() {
-            if let Some(entry_block) = sub.term.blocks.get(0) {
+            if let Some(entry_block) = sub.term.blocks.first() {
                 sub_to_entry_blocks_map.insert(sub.tid.clone(), entry_block.tid.clone());
             }
         }

src/cwe_checker_lib/src/checkers/cwe_476/context.rs

@@ -70,7 +70,7 @@ impl<'a> Context<'a> {
         for (node_id, node) in graph.node_references() {
             match node {
                 Node::BlkStart(block, sub) => {
-                    if let Some(def) = block.term.defs.get(0) {
+                    if let Some(def) = block.term.defs.first() {
                         block_start_node_map.insert((def.tid.clone(), sub.tid.clone()), node_id);
                     }
                 }

src/cwe_checker_lib/src/checkers/cwe_78.rs

@@ -158,7 +158,7 @@ pub fn check_system_call_parameter(
     if let Some(Arg::Register {
         expr: Expression::Var(var),
         ..
-    }) = system_symbol.parameters.get(0)
+    }) = system_symbol.parameters.first()
     {
         if let Some(value) = source_state.get_variable_to_pointer_map().get(var) {
             let contains_string_constant = value.get_absolute_value().is_some();