From 972388a01903b693795004f7720f43df8231fa46 Mon Sep 17 00:00:00 2001
From: Jimmy Cuadra <jimmy@jimmycuadra.com>
Date: Fri, 12 Jul 2019 02:55:49 -0700
Subject: [PATCH] Document error conditions for `redact`.

---
 src/functions.rs | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/functions.rs b/src/functions.rs
index 7390a566..b0279309 100644
--- a/src/functions.rs
+++ b/src/functions.rs
@@ -706,6 +706,16 @@ fn canonical_json_with_fields_to_remove(value: &Value, fields: &[&str]) -> Resul
 /// # Parameters
 ///
 /// * value: A JSON object to redact.
+///
+/// # Errors
+///
+/// Returns an error if:
+///
+/// * `value` is not a JSON object.
+/// * `value` contains a field called `content` that is not a JSON object.
+/// * `value` contains a field called `hashes` that is not a JSON object.
+/// * `value` contains a field called `signatures` that is not a JSON object.
+/// * `value` is missing the `type` field or the field is not a JSON string.
 pub fn redact(value: &Value) -> Result<Value, Error> {
     if !value.is_object() {
         return Err(Error::new("JSON value must be a JSON object"));