move contents of taskchampion repo to tc/

rust/cli/src/argparse/config.rs

@@ -0,0 +1,44 @@
+use super::args::{any, arg_matching, literal};
+use super::ArgList;
+use crate::usage;
+use nom::{branch::alt, combinator::*, sequence::*, IResult};
+
+#[derive(Debug, PartialEq)]
+/// A config operation
+pub(crate) enum ConfigOperation {
+    /// Set a configuration value
+    Set(String, String),
+    /// Show configuration path
+    Path,
+}
+
+impl ConfigOperation {
+    pub(super) fn parse(input: ArgList) -> IResult<ArgList, ConfigOperation> {
+        fn set_to_op(input: (&str, &str, &str)) -> Result<ConfigOperation, ()> {
+            Ok(ConfigOperation::Set(input.1.to_owned(), input.2.to_owned()))
+        }
+        fn path_to_op(_: &str) -> Result<ConfigOperation, ()> {
+            Ok(ConfigOperation::Path)
+        }
+        alt((
+            map_res(
+                tuple((
+                    arg_matching(literal("set")),
+                    arg_matching(any),
+                    arg_matching(any),
+                )),
+                set_to_op,
+            ),
+            map_res(arg_matching(literal("path")), path_to_op),
+        ))(input)
+    }
+
+    pub(super) fn get_usage(u: &mut usage::Usage) {
+        u.subcommands.push(usage::Subcommand {
+            name: "config set",
+            syntax: "config set <key> <value>",
+            summary: "Set a configuration value",
+            description: "Update Taskchampion configuration file to set key = value",
+        });
+    }
+}