cmd/shfmt: Add support for minify and simplify via EditorConfig

Closes #819.

cmd/shfmt/main.go

@@ -380,6 +380,10 @@ func propsOptions(lang syntax.LangVariant, props editorconfig.Section) {
 	syntax.KeepPadding(props.Get("keep_padding") == "true")(printer)
 	// TODO(v4): rename to func_next_line for consistency with flags
 	syntax.FunctionNextLine(props.Get("function_next_line") == "true")(printer)
+	minify_opt := minify.val || props.Get("minify") == "true"
+	syntax.Minify(minify_opt)(printer)
+	// Keep the original value if passed by CLI, or minify is enabled, or it is in the config file
+	simplify.val = simplify.val || minify_opt || props.Get("simplify") == "true"
 }
 
 func formatPath(path string, checkShebang bool) error {

cmd/shfmt/testdata/script/editorconfig.txtar

@@ -159,6 +159,12 @@ keep_padding = true
 [function_next_line.sh]
 function_next_line = true
 
+[simplify.sh]
+simplify = true
+
+[minify.sh]
+minify = true
+
 -- otherknobs/shell_variant_bash.sh --
 array=(elem)
 -- otherknobs/shell_variant_mksh.sh --
@@ -183,6 +189,14 @@ foo()
 {
 	echo foo
 }
+-- otherknobs/simplify.sh --
+foo() {
+	((bar))
+}
+-- otherknobs/minify.sh --
+foo(){
+((bar))
+}
 -- ignored/.editorconfig --
 root = true