config: fix setting of zero-value time.Duration config values

When using section.MapTo(struct) (go-ini), if the struct has a default
value for a time.Duration type, a zero-value in the config will not
overwrite the default. If the type is *time.Duration, it will be
overwritten properly. One consideration was to change all
time.Duration types to *time.Duration. This method was chosen for ease
of implementation.

For example, if you set dirlist-delay = 0s, the delay will be 200ms.
This can be observed by logging the value just after mapping the ui
section in config.go. A config value of 0.1ms will have a delay of
0.1ms.

Currently, aerc has 4 time.Duration config values:
1. DirlistDelay - default 200 ms
2. CompletionDelay - default 250 ms
3. CheckMail - default unset (0)
4. CheckMailTimeout - default 10 s

1, 2, and 4 have a non-zero default value and are subject to this bug.
Only 1 and 2 are fixed in this patch. Number 4 would not make sense to
have a 0 second timeout, therefore we can prevent the user from doing
this by keeping it as it is.

Another option could be to set these to 0 in config.go. The default
config (aerc.conf) has these keys in it with their default values.
Presumably, we don't need to set them again in config.go. If a user
deletes the config values out of aerc.conf, the UI will function but
with 0s delays.

Signed-off-by: Tim Culverhouse <tim@timculverhouse.com>
Tested-by: Moritz Poldrack <moritz@poldrack.dev>

1 files changed, 19 insertions, 0 deletions

diff --git a/config/config.go b/config/config.go
index 6410632..941a726 100644
--- a/config/config.go
+++ b/config/config.go
@@ -467,6 +467,25 @@ func (config *AercConfig) LoadConfig(file *ini.File) error {
 		if err := validateBorderChars(ui, &config.Ui); err != nil {
 			return err
 		}
+		// Values with type=time.Duration must be explicitly set. If these
+		// values are given a default in the struct passed to ui.MapTo, which
+		// they are, a zero-value in the config won't overwrite the default.
+		for key, val := range ui.KeysHash() {
+			switch key {
+			case "dirlist-delay":
+				dur, err := time.ParseDuration(val)
+				if err != nil {
+					return err
+				}
+				config.Ui.DirListDelay = dur
+			case "completion-delay":
+				dur, err := time.ParseDuration(val)
+				if err != nil {
+					return err
+				}
+				config.Ui.CompletionDelay = dur
+			}
+		}
 	}
 
 	for _, sectionName := range file.SectionStrings() {