diff --git a/pkg/gui/main_view_render.go b/pkg/gui/main_view_render.go
index b375532ef..a0ba8ddca 100644
--- a/pkg/gui/main_view_render.go
+++ b/pkg/gui/main_view_render.go
@@ -112,6 +112,8 @@ type runRender func(spec renderSpec) (startRender, onCloseRender)
 // view, running the command the given way. key names what is rendered, so that
 // a re-render of the same content can be told from a render of other content.
 func (gui *Gui) newTaskForRender(spec renderSpec, prefix string, key string, run runRender) error {
+	setColumnsEnvVar(spec.cmd, spec.width)
+
 	start, onClose := run(spec)
 
 	manager := gui.getManager(spec.view)
@@ -119,6 +121,15 @@ func (gui *Gui) newTaskForRender(spec renderSpec, prefix string, key string, run
 	return manager.NewTask(manager.NewCmdTask(start, prefix, linesToRead, onClose), key)
 }
 
+// setColumnsEnvVar tells a command how wide the view its output goes into is.
+// git reads COLUMNS in preference to the size of the terminal it is talking to,
+// and lays the diffstat graph out to it; a diff renderer with no terminal to
+// ask may read it too (difftastic and diff-so-fancy do, delta does not). A
+// command told nothing renders for 80 columns.
+func setColumnsEnvVar(cmd *exec.Cmd, width int) {
+	cmd.Env = append(cmd.Env, fmt.Sprintf("COLUMNS=%d", width))
+}
+
 func removeExistingTermEnvVars(env []string) []string {
 	return lo.Filter(env, func(envVar string, _ int) bool {
 		return !isTermEnvVar(envVar)
diff --git a/pkg/integration/tests/diff/stat_uses_the_view_width.go b/pkg/integration/tests/diff/stat_uses_the_view_width.go
index 304f20d0d..b75379bee 100644
--- a/pkg/integration/tests/diff/stat_uses_the_view_width.go
+++ b/pkg/integration/tests/diff/stat_uses_the_view_width.go
@@ -37,9 +37,6 @@ var StatUsesTheViewWidth = NewIntegrationTest(NewIntegrationTestArgs{
 			)
 
 		t.Views().Main().
-			/* EXPECTED:
 			Content(MatchesRegexp(`(?m)^ file1 \| 200 \+{80,}$`))
-			ACTUAL: */
-			Content(MatchesRegexp(`(?m)^ file1 \| 200 \+{60,70}$`))
 	},
 })