diff --git a/testing/python/approx.py b/testing/python/approx.py
index 6f20ac571..3b87e58f9 100644
--- a/testing/python/approx.py
+++ b/testing/python/approx.py
@@ -289,15 +289,15 @@ class TestApprox:
             a,
             b,
             [
-                r"  ",
-                r"  comparison failed. Mismatched elements: 20 / 20:",
-                rf"  Max absolute difference: {SOME_FLOAT}",
-                rf"  Max relative difference: {SOME_FLOAT}",
-                r"  Index \| Obtained\s+\| Expected",
-                rf"  \(0,\)\s+\| {SOME_FLOAT} \| {SOME_FLOAT} ± {SOME_FLOAT}",
-                rf"  \(1,\)\s+\| {SOME_FLOAT} \| {SOME_FLOAT} ± {SOME_FLOAT}...",
-                "",
-                rf"\s*...Full output truncated \({SOME_INT} lines hidden\), use '-vv' to show",
+                r"^  $",
+                r"^  comparison failed. Mismatched elements: 20 / 20:$",
+                rf"^  Max absolute difference: {SOME_FLOAT}$",
+                rf"^  Max relative difference: {SOME_FLOAT}$",
+                r"^  Index \| Obtained\s+\| Expected\s+$",
+                rf"^  \(0,\)\s+\| {SOME_FLOAT} \| {SOME_FLOAT} ± {SOME_FLOAT}e-{SOME_INT}$",
+                rf"^  \(1,\)\s+\| {SOME_FLOAT} \| {SOME_FLOAT} ± {SOME_FLOAT}e-{SOME_INT}\.\.\.$",
+                "^  $",
+                rf"^  ...Full output truncated \({SOME_INT} lines hidden\), use '-vv' to show$",
             ],
             verbosity_level=0,
         )