diff --git a/contrib/simplemerge b/contrib/simplemerge
--- a/contrib/simplemerge
+++ b/contrib/simplemerge
@@ -97,13 +97,18 @@
     base_input = simplemerge.MergeInput(
         context.arbitraryfilectx(base), labels[2]
     )
+    ui = uimod.ui.load()
+    opts = pycompat.strkwargs(opts)
+    try:
+        local_input.verifytext(ui, **opts)
+        base_input.verifytext(ui, **opts)
+        other_input.verifytext(ui, **opts)
+    except error.Abort:
+        sys.exit(1)
+
     sys.exit(
         simplemerge.simplemerge(
-            uimod.ui.load(),
-            local_input,
-            base_input,
-            other_input,
-            **pycompat.strkwargs(opts)
+            ui, local_input, base_input, other_input, **opts
         )
     )
 except ParseError as e:
diff --git a/mercurial/filemerge.py b/mercurial/filemerge.py
--- a/mercurial/filemerge.py
+++ b/mercurial/filemerge.py
@@ -429,9 +429,14 @@
             mode = b'mergediff'
         elif premerge == b'keep-merge3':
             mode = b'merge3'
-        r = simplemerge.simplemerge(
-            ui, local, base, other, quiet=True, mode=mode
-        )
+        try:
+            local.verifytext(ui, quiet=True)
+            base.verifytext(ui, quiet=True)
+            other.verifytext(ui, quiet=True)
+        except error.Abort:
+            r = True
+        else:
+            r = simplemerge.simplemerge(ui, local, base, other, mode=mode)
         if not r:
             ui.debug(b" premerge successful\n")
             return 0
@@ -470,7 +475,14 @@
     of merge, unless mode equals 'union' which suppresses the markers."""
     ui = repo.ui
 
-    r = simplemerge.simplemerge(ui, local, base, other, mode=mode)
+    try:
+        local.verifytext(ui)
+        base.verifytext(ui)
+        other.verifytext(ui)
+    except error.Abort:
+        r = True
+    else:
+        r = simplemerge.simplemerge(ui, local, base, other, mode=mode)
     return True, r, False
 
 
diff --git a/mercurial/simplemerge.py b/mercurial/simplemerge.py
--- a/mercurial/simplemerge.py
+++ b/mercurial/simplemerge.py
@@ -493,7 +493,6 @@
                 ui.warn(_(b'warning: %s\n') % msg)
             if not opts.get('text'):
                 raise error.Abort(msg)
-        return text
 
 
 def simplemerge(ui, local, base, other, **opts):
@@ -502,14 +501,7 @@
     The merged result is written into `localctx`.
     """
 
-    try:
-        localtext = local.verifytext(ui, **opts)
-        basetext = base.verifytext(ui, **opts)
-        othertext = other.verifytext(ui, **opts)
-    except error.Abort:
-        return True
-
-    m3 = Merge3Text(basetext, localtext, othertext)
+    m3 = Merge3Text(base.text(), local.text(), other.text())
     conflicts = False
     mode = opts.get('mode', b'merge')
     if mode == b'union':