diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 36de16e..21a4dee 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -67,7 +67,7 @@ jobs:
     - name: No-default features
       run: cargo test --workspace --no-default-features
   msrv:
-    name: "Check MSRV: 1.40.0"
+    name: "Check MSRV: 1.54.0"
     needs: smoke
     runs-on: ubuntu-latest
     steps:
@@ -76,7 +76,7 @@ jobs:
     - name: Install Rust
       uses: actions-rs/toolchain@v1
       with:
-        toolchain: 1.40.0  # MSRV
+        toolchain: 1.54.0  # MSRV
         profile: minimal
         override: true
     - uses: Swatinem/rust-cache@v1
@@ -129,7 +129,7 @@ jobs:
     - name: Install Rust
       uses: actions-rs/toolchain@v1
       with:
-        toolchain: 1.40.0  # MSRV
+        toolchain: 1.54.0  # MSRV
         profile: minimal
         override: true
         components: clippy
diff --git a/.github/workflows/rust-next.yml b/.github/workflows/rust-next.yml
index 95e7914..af71a19 100644
--- a/.github/workflows/rust-next.yml
+++ b/.github/workflows/rust-next.yml
@@ -57,9 +57,9 @@ jobs:
     strategy:
       matrix:
         rust:
-        - 1.44.0  # MSRV
+        - 1.54.0  # MSRV
         - stable
-    continue-on-error: ${{ matrix.rust != '1.44.0' }}  # MSRV
+    continue-on-error: ${{ matrix.rust != '1.54.0' }}  # MSRV
     runs-on: ubuntu-latest
     steps:
     - name: Checkout repository
diff --git a/crates/tree/examples/failures.rs b/crates/tree/examples/failures.rs
index ffdf386..9ba640c 100644
--- a/crates/tree/examples/failures.rs
+++ b/crates/tree/examples/failures.rs
@@ -12,7 +12,7 @@ fn main() {
 
     let expected = [1, 2, 3];
     let actual = 15;
-    let pred = predicates::iter::in_iter(expected);
+    let pred = predicates::iter::in_iter(IntoIterator::into_iter(expected));
     if let Some(case) = pred.find_case(false, &actual) {
         let tree = case.tree();
         println!("{}", tree);
diff --git a/src/str/normalize.rs b/src/str/normalize.rs
index 893b5b6..9ab3f85 100644
--- a/src/str/normalize.rs
+++ b/src/str/normalize.rs
@@ -11,7 +11,6 @@ use crate::Predicate;
 use std::fmt;
 
 use normalize_line_endings::normalized;
-use std::iter::FromIterator;
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 /// Predicate adapter that normalizes the newlines contained in the variable being tested.
@@ -39,12 +38,12 @@ where
     P: Predicate<str>,
 {
     fn eval(&self, variable: &str) -> bool {
-        self.p
-            .eval(&String::from_iter(normalized(variable.chars())))
+        let variable = normalized(variable.chars()).collect::<String>();
+        self.p.eval(&variable)
     }
 
     fn find_case<'a>(&'a self, expected: bool, variable: &str) -> Option<reflection::Case<'a>> {
-        let variable = String::from_iter(normalized(variable.chars()));
+        let variable = normalized(variable.chars()).collect::<String>();
         self.p.find_case(expected, &variable)
     }
 }