tool: Drop dependency on promptly.

  - Do not ask whether to overwrite files, just fail and mention
    --force.

  - We decided that sq should not be interactive (modulo password
    prompts).  Interactive programs are more difficult to test and
    script.  Furthermore, it turns out that nix, a dependency of
    promptly, does not build on Android.

  - Fixes #148.

3 files changed, 4 insertions, 11 deletions

diff --git a/tool/Cargo.toml b/tool/Cargo.toml
index 9d55e381..7fd56ac2 100644
--- a/tool/Cargo.toml
+++ b/tool/Cargo.toml
@@ -31,7 +31,6 @@ prettytable-rs = "0.8.0"
 rpassword = "2.0.0"
 tempfile = "3.0.4"
 time = "0.1.38"
-promptly = "0.1.5"
 
 [build-dependencies]
 clap = "2.27.1"
diff --git a/tool/src/sq.rs b/tool/src/sq.rs
index 244fecf9..d70d9d10 100644
--- a/tool/src/sq.rs
+++ b/tool/src/sq.rs
@@ -7,7 +7,6 @@ extern crate prettytable;
 extern crate rpassword;
 extern crate tempfile;
 extern crate time;
-extern crate promptly;
 
 use failure::ResultExt;
 use prettytable::{Table, Cell, Row};
@@ -41,17 +40,12 @@ fn open_or_stdin(f: Option<&str>) -> Result<Box<io::Read>, failure::Error> {
 
 fn create_or_stdout(f: Option<&str>, force: bool)
     -> Result<Box<io::Write>, failure::Error> {
-    use promptly::prompt_default;
-
     match f {
         None => Ok(Box::new(io::stdout())),
         Some(p) if p == "-" => Ok(Box::new(io::stdout())),
         Some(f) => {
             let p = Path::new(f);
-            let path_ok = force || !p.exists() ||
-                prompt_default(format!("{} exists already. Overwrite?", f), false);
-
-            if path_ok {
+            if !p.exists() || force {
                 Ok(Box::new(OpenOptions::new()
                             .write(true)
                             .truncate(true)
@@ -59,8 +53,8 @@ fn create_or_stdout(f: Option<&str>, force: bool)
                             .open(f)
                             .context("Failed to create output file")?))
             } else {
-                eprintln!("Cannot continue");
-                exit(1);
+                Err(failure::err_msg(
+                    format!("File {:?} exists, use --force to overwrite", p)))
             }
         }
     }
diff --git a/tool/src/sq_cli.rs b/tool/src/sq_cli.rs
index 78a9b484..b44403fc 100644
--- a/tool/src/sq_cli.rs
+++ b/tool/src/sq_cli.rs
@@ -29,7 +29,7 @@ pub fn build() -> App<'static, 'static> {
         .arg(Arg::with_name("force")
              .long("force")
              .short("f")
-             .help("Overwrite files without asking"))
+             .help("Overwrite existing files"))
         .subcommand(SubCommand::with_name("decrypt")
                     .display_order(10)
                     .about("Decrypts an OpenPGP message")