diff --git a/sjsonnet/src/sjsonnet/Format.scala b/sjsonnet/src/sjsonnet/Format.scala
index 99a9e1de..58dcdacf 100644
--- a/sjsonnet/src/sjsonnet/Format.scala
+++ b/sjsonnet/src/sjsonnet/Format.scala
@@ -725,41 +725,21 @@ object Format {
                   )
               }
             case _: Val.True =>
-              val b = 1
               formatted.conversion match {
-                case 'd' | 'i' | 'u' => formatInteger(formatted, b)
-                case 'o'             => formatOctal(formatted, b)
-                case 'x'             => formatHexadecimal(formatted, b)
-                case 'X'             => formatHexadecimal(formatted, b).toUpperCase
-                case 'e'             => formatExponent(formatted, b).toLowerCase
-                case 'E'             => formatExponent(formatted, b)
-                case 'f' | 'F'       => formatFloat(formatted, b)
-                case 'g'             => formatGeneric(formatted, b).toLowerCase
-                case 'G'             => formatGeneric(formatted, b)
-                case 'c'             =>
-                  Error.fail("%c expected number or string, got boolean")
                 case 's' => widenRaw(formatted, "true")
-                case _   =>
+                case 'c' =>
+                  Error.fail("%c expected number or string, got boolean")
+                case _ =>
                   Error.fail(
                     "expected number or string at position %d, got boolean".format(i)
                   )
               }
             case _: Val.False =>
-              val b = 0
               formatted.conversion match {
-                case 'd' | 'i' | 'u' => formatInteger(formatted, b)
-                case 'o'             => formatOctal(formatted, b)
-                case 'x'             => formatHexadecimal(formatted, b)
-                case 'X'             => formatHexadecimal(formatted, b).toUpperCase
-                case 'e'             => formatExponent(formatted, b).toLowerCase
-                case 'E'             => formatExponent(formatted, b)
-                case 'f' | 'F'       => formatFloat(formatted, b)
-                case 'g'             => formatGeneric(formatted, b).toLowerCase
-                case 'G'             => formatGeneric(formatted, b)
-                case 'c'             =>
-                  Error.fail("%c expected number or string, got boolean")
                 case 's' => widenRaw(formatted, "false")
-                case _   =>
+                case 'c' =>
+                  Error.fail("%c expected number or string, got boolean")
+                case _ =>
                   Error.fail(
                     "expected number or string at position %d, got boolean".format(i)
                   )
diff --git a/sjsonnet/test/resources/new_test_suite/error.format_d_boolean.jsonnet b/sjsonnet/test/resources/new_test_suite/error.format_d_boolean.jsonnet
new file mode 100644
index 00000000..956cc3db
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/error.format_d_boolean.jsonnet
@@ -0,0 +1 @@
+"%d" % true
diff --git a/sjsonnet/test/resources/new_test_suite/error.format_d_boolean.jsonnet.golden b/sjsonnet/test/resources/new_test_suite/error.format_d_boolean.jsonnet.golden
new file mode 100644
index 00000000..5b469bea
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/error.format_d_boolean.jsonnet.golden
@@ -0,0 +1,2 @@
+sjsonnet.Error: [std.format] expected number or string at position 0, got boolean
+    at [<root>].(error.format_d_boolean.jsonnet:1:6)
diff --git a/sjsonnet/test/resources/new_test_suite/error.format_e_boolean.jsonnet b/sjsonnet/test/resources/new_test_suite/error.format_e_boolean.jsonnet
new file mode 100644
index 00000000..c8d83ee1
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/error.format_e_boolean.jsonnet
@@ -0,0 +1 @@
+"%e" % true
diff --git a/sjsonnet/test/resources/new_test_suite/error.format_e_boolean.jsonnet.golden b/sjsonnet/test/resources/new_test_suite/error.format_e_boolean.jsonnet.golden
new file mode 100644
index 00000000..71a81f07
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/error.format_e_boolean.jsonnet.golden
@@ -0,0 +1,2 @@
+sjsonnet.Error: [std.format] expected number or string at position 0, got boolean
+    at [<root>].(error.format_e_boolean.jsonnet:1:6)
diff --git a/sjsonnet/test/resources/new_test_suite/error.format_f_boolean.jsonnet b/sjsonnet/test/resources/new_test_suite/error.format_f_boolean.jsonnet
new file mode 100644
index 00000000..152d64e2
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/error.format_f_boolean.jsonnet
@@ -0,0 +1 @@
+"%f" % false
diff --git a/sjsonnet/test/resources/new_test_suite/error.format_f_boolean.jsonnet.golden b/sjsonnet/test/resources/new_test_suite/error.format_f_boolean.jsonnet.golden
new file mode 100644
index 00000000..3a56f65b
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/error.format_f_boolean.jsonnet.golden
@@ -0,0 +1,2 @@
+sjsonnet.Error: [std.format] expected number or string at position 0, got boolean
+    at [<root>].(error.format_f_boolean.jsonnet:1:6)
diff --git a/sjsonnet/test/resources/new_test_suite/error.format_g_boolean.jsonnet b/sjsonnet/test/resources/new_test_suite/error.format_g_boolean.jsonnet
new file mode 100644
index 00000000..a7f4d5a8
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/error.format_g_boolean.jsonnet
@@ -0,0 +1 @@
+"%g" % true
diff --git a/sjsonnet/test/resources/new_test_suite/error.format_g_boolean.jsonnet.golden b/sjsonnet/test/resources/new_test_suite/error.format_g_boolean.jsonnet.golden
new file mode 100644
index 00000000..18635540
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/error.format_g_boolean.jsonnet.golden
@@ -0,0 +1,2 @@
+sjsonnet.Error: [std.format] expected number or string at position 0, got boolean
+    at [<root>].(error.format_g_boolean.jsonnet:1:6)
diff --git a/sjsonnet/test/resources/new_test_suite/error.format_o_boolean.jsonnet b/sjsonnet/test/resources/new_test_suite/error.format_o_boolean.jsonnet
new file mode 100644
index 00000000..7084a080
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/error.format_o_boolean.jsonnet
@@ -0,0 +1 @@
+"%o" % true
diff --git a/sjsonnet/test/resources/new_test_suite/error.format_o_boolean.jsonnet.golden b/sjsonnet/test/resources/new_test_suite/error.format_o_boolean.jsonnet.golden
new file mode 100644
index 00000000..68524ca8
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/error.format_o_boolean.jsonnet.golden
@@ -0,0 +1,2 @@
+sjsonnet.Error: [std.format] expected number or string at position 0, got boolean
+    at [<root>].(error.format_o_boolean.jsonnet:1:6)
diff --git a/sjsonnet/test/resources/new_test_suite/error.format_x_boolean.jsonnet b/sjsonnet/test/resources/new_test_suite/error.format_x_boolean.jsonnet
new file mode 100644
index 00000000..e7827689
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/error.format_x_boolean.jsonnet
@@ -0,0 +1 @@
+"%x" % true
diff --git a/sjsonnet/test/resources/new_test_suite/error.format_x_boolean.jsonnet.golden b/sjsonnet/test/resources/new_test_suite/error.format_x_boolean.jsonnet.golden
new file mode 100644
index 00000000..18821057
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/error.format_x_boolean.jsonnet.golden
@@ -0,0 +1,2 @@
+sjsonnet.Error: [std.format] expected number or string at position 0, got boolean
+    at [<root>].(error.format_x_boolean.jsonnet:1:6)
diff --git a/sjsonnet/test/resources/new_test_suite/format_boolean_string_only.jsonnet b/sjsonnet/test/resources/new_test_suite/format_boolean_string_only.jsonnet
new file mode 100644
index 00000000..8ff86e9d
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/format_boolean_string_only.jsonnet
@@ -0,0 +1,9 @@
+// Regression test: %s must still work with booleans after the type-error fix.
+// Verified against cpp-jsonnet 0.21.0, go-jsonnet 0.22.0, jrsonnet 0.5.0-pre99.
+std.assertEqual("%s" % true, "true") &&
+std.assertEqual("%s" % false, "false") &&
+std.assertEqual("%10s" % true, "      true") &&
+std.assertEqual("%-10s" % false, "false     ") &&
+std.assertEqual("val: %s" % true, "val: true") &&
+std.assertEqual("%s %s" % [true, false], "true false") &&
+true
diff --git a/sjsonnet/test/resources/new_test_suite/format_boolean_string_only.jsonnet.golden b/sjsonnet/test/resources/new_test_suite/format_boolean_string_only.jsonnet.golden
new file mode 100644
index 00000000..27ba77dd
--- /dev/null
+++ b/sjsonnet/test/resources/new_test_suite/format_boolean_string_only.jsonnet.golden
@@ -0,0 +1 @@
+true