From 5029d3c4bbb1d03ae36ac5720c47dec79478feed Mon Sep 17 00:00:00 2001
From: Eric <5846501+ericphanson@users.noreply.github.com>
Date: Mon, 8 Jul 2019 19:51:06 -0500
Subject: [PATCH] Add comment

---
 deps/build.jl | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/deps/build.jl b/deps/build.jl
index 61c75f27..6e99dbed 100644
--- a/deps/build.jl
+++ b/deps/build.jl
@@ -65,7 +65,11 @@ if use_bp
 else
     @info("Using system `ffmpeg`. If you run into `ffmpeg`-related trouble, trying running `ENV[\"PLOTS_INSTALL_FFMPEG\"]=\"true\"; using Pkg; Pkg.build(\"Plots\")` to use `BinaryProvider`-provided `ffmpeg` instead.")
 
-    
+    # if we're using the system `ffmpeg`, remove `binary_provider_deps.jl`,
+    # so the existence of that file is equivalent to using BinaryProvider. 
+    # This lets us check if the file exists to know whether or not to 
+    # call `check_deps` in `__init__()`, and to set the system fallback
+    # `const ffmpeg = "ffmpeg"` in Plots.jl.
     if isfile("binary_provider_deps.jl")
         rm("binary_provider_deps.jl")
     end