variable=value overrides done

justfile

@@ -13,6 +13,8 @@ build:
 check:
 	cargo check
 
+nop:
+
 publish: clippy build
 	# make sure version is up to date
 	git diff --no-ext-diff --quiet --exit-code

notes

@@ -7,13 +7,7 @@ notes
   - test values of interpolations
   - test results of concatination
   - test string escape parsing
-
-- --debug mode will evaluate everything and print values after assignments and interpolation expressions
-  . should it evaluate `` in recipes?
-
-- set variables from the command line:
-  . j --set build linux
-  . j build=linux
+  - should it evaluate `` in recipes?
 
 - before release:
 
@@ -39,6 +33,8 @@ notes
   . clean
   . update logs (repetitive git flow)
 - full documentation
+  . man page
+  . record sessions and replay them to output docs
   . talk about why the syntax is so unforgiving
     easier to accept a program that you once rejected than to
     no longer accept a program or change its meaning
@@ -71,4 +67,9 @@ enhancements:
   . just xyz/foo # xyz/justfile:foo
   . just xyz/    # xyz/justfile:DEFAULT
 - allow setting and exporting environment variables
+  . export a as "HELLO_BAR"
+  . export a
+  . export HELLO_BAR = a
+  . export CC_FLAGS = "-g"
+  . will have to support crazy names
 - indentation or slash for line continuation in plain recipes

src/app.rs

@@ -1,6 +1,8 @@
 extern crate clap;
+extern crate regex;
 
 use std::{io, fs, env, process};
+use std::collections::BTreeMap;
 use self::clap::{App, Arg};
 use super::Slurp;
 
@@ -37,6 +39,13 @@ pub fn app() {
          .takes_value(true)
          .value_name("recipe")
          .help("Show information about <recipe>"))
+    .arg(Arg::with_name("set")
+         .long("set")
+         .takes_value(true)
+         .number_of_values(2)
+         .value_names(&["variable", "value"])
+         .multiple(true)
+         .help("set <variable> to <value>"))
     .arg(Arg::with_name("working-directory")
          .long("working-directory")
          .takes_value(true)
@@ -123,15 +132,37 @@ pub fn app() {
     }
   }
 
+  let set_count = matches.occurrences_of("set");
+  let mut overrides = BTreeMap::new();
+  if set_count > 0 {
+    let mut values = matches.values_of("set").unwrap();
+    for _ in 0..set_count {
+      overrides.insert(values.next().unwrap(), values.next().unwrap());
+    }
+  }
+
+  let override_re = regex::Regex::new("^([^=]+)=(.*)$").unwrap();
+
   let arguments = if let Some(arguments) = matches.values_of("arguments") {
-    arguments.collect::<Vec<_>>()
+    let mut done = false;
+    let mut rest = vec![];
+    for argument in arguments {
+      if !done && override_re.is_match(argument) {
+        let captures = override_re.captures(argument).unwrap();
+        overrides.insert(captures.at(1).unwrap(), captures.at(2).unwrap());
+      } else {
+        rest.push(argument);
+        done = true;
+      }
+    }
+    rest
   } else if let Some(recipe) = justfile.first() {
     vec![recipe]
   } else {
     die!("Justfile contains no recipes");
   };
 
-  if let Err(run_error) = justfile.run(&arguments) {
+  if let Err(run_error) = justfile.run(&overrides, &arguments) {
     warn!("{}", run_error);
     match run_error {
       super::RunError::Code{code, ..        } => process::exit(code),

src/integration.rs

@@ -349,3 +349,52 @@ a = `exit 222`",
 ",
   );
 }
+
+#[test]
+fn unknown_override_options() {
+  integration_test(
+    "unknown_override_options",
+    &["--set", "foo", "bar", "a", "b", "--set", "baz", "bob", "--set", "a", "b"],
+    "foo:
+ echo hello
+ echo {{`exit 111`}}
+a = `exit 222`",
+    255,
+    "",
+    "baz and foo set on the command line but not present in justfile\n",
+  );
+}
+
+#[test]
+fn unknown_override_args() {
+  integration_test(
+    "unknown_override_args",
+    &["foo=bar", "baz=bob", "a=b", "a", "b"],
+    "foo:
+ echo hello
+ echo {{`exit 111`}}
+a = `exit 222`",
+    255,
+    "",
+    "baz and foo set on the command line but not present in justfile\n",
+  );
+}
+
+#[test]
+fn overrides_first() {
+  integration_test(
+    "unknown_override_args",
+    &["foo=bar", "a=b", "recipe", "baz=bar"],
+    r#"
+foo = "foo"
+a = "a"
+baz = "baz"
+    
+recipe arg:
+ echo arg={{arg}}
+ echo {{foo + a + baz}}"#,
+    0,
+    "arg=baz=bar\nbarbbaz\n",
+    "echo arg=baz=bar\necho barbbaz\n",
+  );
+}

src/lib.rs

@@ -197,6 +197,7 @@ impl<'a> Recipe<'a> {
       evaluated:   BTreeMap::new(),
       scope:       scope,
       assignments: &BTreeMap::new(),
+      overrides:   &BTreeMap::new(),
     };
 
     if self.shebang {
@@ -494,11 +495,13 @@ impl<'a: 'b, 'b> AssignmentResolver<'a, 'b> {
 
 fn evaluate_assignments<'a>(
   assignments: &BTreeMap<&'a str, Expression<'a>>,
+  overrides:   &BTreeMap<&str, &str>,
 ) -> Result<BTreeMap<&'a str, String>, RunError<'a>> {
   let mut evaluator = Evaluator {
-    evaluated:         BTreeMap::new(),
-    scope:             &BTreeMap::new(),
-    assignments:       assignments,
+    evaluated:   BTreeMap::new(),
+    scope:       &BTreeMap::new(),
+    assignments: assignments,
+    overrides:   overrides,
   };
 
   for name in assignments.keys() {
@@ -512,6 +515,7 @@ struct Evaluator<'a: 'b, 'b> {
   evaluated:   BTreeMap<&'a str, String>,
   scope:       &'b BTreeMap<&'a str, String>,
   assignments: &'b BTreeMap<&'a str, Expression<'a>>,
+  overrides:   &'b BTreeMap<&'b str, &'b str>,
 }
 
 impl<'a, 'b> Evaluator<'a, 'b> {
@@ -538,8 +542,12 @@ impl<'a, 'b> Evaluator<'a, 'b> {
     }
 
     if let Some(expression) = self.assignments.get(name) {
-      let value = try!(self.evaluate_expression(expression, &BTreeMap::new()));
-      self.evaluated.insert(name, value);
+      if let Some(value) = self.overrides.get(name) {
+        self.evaluated.insert(name, value.to_string());
+      } else {
+        let value = try!(self.evaluate_expression(expression, &BTreeMap::new()));
+        self.evaluated.insert(name, value);
+      }
     } else {
       return Err(RunError::InternalError { 
         message: format!("attempted to evaluated unknown assignment {}", name)
@@ -635,26 +643,41 @@ fn mixed_whitespace(text: &str) -> bool {
   !(text.chars().all(|c| c == ' ') || text.chars().all(|c| c == '\t'))
 }
 
-struct Or<'a, T: 'a + Display>(&'a [T]);
+struct And<'a, T: 'a + Display>(&'a [T]);
+struct Or <'a, T: 'a + Display>(&'a [T]);
+
+impl<'a, T: Display> Display for And<'a, T> {
+  fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+    conjoin(f, self.0, "and")
+  }
+}
 
 impl<'a, T: Display> Display for Or<'a, T> {
   fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
-    match self.0.len() {
+    conjoin(f, self.0, "or")
+  }
+}
+
+fn conjoin<T: Display>(
+  f:           &mut fmt::Formatter,
+  values:      &[T],
+  conjunction: &str,
+) -> Result<(), fmt::Error> {
+    match values.len() {
       0 => {},
-      1 => try!(write!(f, "{}", self.0[0])),
-      2 => try!(write!(f, "{} or {}", self.0[0], self.0[1])),
-      _ => for (i, item) in self.0.iter().enumerate() {
+      1 => try!(write!(f, "{}", values[0])),
+      2 => try!(write!(f, "{} {} {}", values[0], conjunction, values[1])),
+      _ => for (i, item) in values.iter().enumerate() {
         try!(write!(f, "{}", item));
-        if i == self.0.len() - 1 {
-        } else if i == self.0.len() - 2 {
-          try!(write!(f, ", or "));
+        if i == values.len() - 1 {
+        } else if i == values.len() - 2 {
+          try!(write!(f, ", {} ", conjunction));
         } else {
           try!(write!(f, ", "))
         }
       },
     }
     Ok(())
-  }
 }
 
 impl<'a> Display for Error<'a> {
@@ -783,8 +806,20 @@ impl<'a, 'b> Justfile<'a> where 'a: 'b {
     self.recipes.keys().cloned().collect()
   }
 
-  fn run(&'a self, arguments: &[&'a str]) -> Result<(), RunError<'a>> {
-    let scope = try!(evaluate_assignments(&self.assignments));
+  fn run(
+    &'a self,
+    overrides: &BTreeMap<&'a str, &'a str>,
+    arguments: &[&'a str]
+  ) -> Result<(), RunError<'a>> {
+    let unknown_overrides = overrides.keys().cloned()
+      .filter(|name| !self.assignments.contains_key(name))
+      .collect::<Vec<_>>();
+
+    if !unknown_overrides.is_empty() {
+      return Err(RunError::UnknownOverrides{overrides: unknown_overrides});
+    }
+
+    let scope = try!(evaluate_assignments(&self.assignments, overrides));
     let mut ran = HashSet::new();
 
     for (i, argument) in arguments.iter().enumerate() {
@@ -878,6 +913,7 @@ enum RunError<'a> {
   TmpdirIoError{recipe: &'a str, io_error: io::Error},
   UnknownFailure{recipe: &'a str},
   UnknownRecipes{recipes: Vec<&'a str>},
+  UnknownOverrides{overrides: Vec<&'a str>},
   BacktickCode{code: i32, token: Token<'a>},
   BacktickIoError{io_error: io::Error},
   BacktickSignal{signal: i32},
@@ -895,6 +931,10 @@ impl<'a> Display for RunError<'a> {
           try!(write!(f, "Justfile does not contain recipes: {}", recipes.join(" ")));
         };
       },
+      RunError::UnknownOverrides{ref overrides} => {
+        try!(write!(f, "{} set on the command line but not present in justfile",
+                    And(overrides)))
+      },
       RunError::NonLeadingRecipeWithArguments{recipe} => {
         try!(write!(f, "Recipe `{}` takes arguments and so must be the first and only recipe specified on the command line", recipe));
       },

src/unit.rs

@@ -1,8 +1,8 @@
 extern crate tempdir;
 
-use super::{Token, Error, ErrorKind, Justfile};
-
+use super::{Token, Error, ErrorKind, Justfile, RunError};
 use super::TokenKind::*;
+use std::collections::BTreeMap;
 
 fn tokenize_success(text: &str, expected_summary: &str) {
   let tokens = super::tokenize(text).unwrap();
@@ -562,18 +562,26 @@ fn mixed_leading_whitespace() {
 }
 
 #[test]
-fn write_or() {
+fn conjoin_or() {
   assert_eq!("1",             super::Or(&[1      ]).to_string());
   assert_eq!("1 or 2",        super::Or(&[1,2    ]).to_string());
   assert_eq!("1, 2, or 3",    super::Or(&[1,2,3  ]).to_string());
   assert_eq!("1, 2, 3, or 4", super::Or(&[1,2,3,4]).to_string());
 }
 
+#[test]
+fn conjoin_and() {
+  assert_eq!("1",             super::And(&[1      ]).to_string());
+  assert_eq!("1 and 2",        super::And(&[1,2    ]).to_string());
+  assert_eq!("1, 2, and 3",    super::And(&[1,2,3  ]).to_string());
+  assert_eq!("1, 2, 3, and 4", super::And(&[1,2,3,4]).to_string());
+}
+
 #[test]
 fn unknown_recipes() {
-  match parse_success("a:\nb:\nc:").run(&["a", "x", "y", "z"]).unwrap_err() {
-    super::RunError::UnknownRecipes{recipes} => assert_eq!(recipes, &["x", "y", "z"]),
-    other @ _ => panic!("expected an unknown recipe error, but got: {}", other),
+  match parse_success("a:\nb:\nc:").run(&BTreeMap::new(), &["a", "x", "y", "z"]).unwrap_err() {
+    RunError::UnknownRecipes{recipes} => assert_eq!(recipes, &["x", "y", "z"]),
+    other => panic!("expected an unknown recipe error, but got: {}", other),
   }
 }
 
@@ -739,8 +747,8 @@ a:
  x
 ";
 
-  match parse_success(text).run(&["a"]).unwrap_err() {
-    super::RunError::Code{recipe, code} => {
+  match parse_success(text).run(&BTreeMap::new(), &["a"]).unwrap_err() {
+    RunError::Code{recipe, code} => {
       assert_eq!(recipe, "a");
       assert_eq!(code, 200);
     },
@@ -750,12 +758,12 @@ a:
 
 #[test]
 fn code_error() {
-  match parse_success("fail:\n @function x { return 100; }; x").run(&["fail"]).unwrap_err() {
-    super::RunError::Code{recipe, code} => {
+  match parse_success("fail:\n @function x { return 100; }; x").run(&BTreeMap::new(), &["fail"]).unwrap_err() {
+    RunError::Code{recipe, code} => {
       assert_eq!(recipe, "fail");
       assert_eq!(code, 100);
     },
-    other @ _ => panic!("expected a code run error, but got: {}", other),
+    other => panic!("expected a code run error, but got: {}", other),
   }
 }
 
@@ -765,8 +773,8 @@ fn run_args() {
 a return code:
  @function x { {{return}} {{code + "0"}}; }; x"#;
 
-  match parse_success(text).run(&["a", "return", "15"]).unwrap_err() {
-    super::RunError::Code{recipe, code} => {
+  match parse_success(text).run(&BTreeMap::new(), &["a", "return", "15"]).unwrap_err() {
+    RunError::Code{recipe, code} => {
       assert_eq!(recipe, "a");
       assert_eq!(code, 150);
     },
@@ -776,8 +784,8 @@ a return code:
 
 #[test]
 fn missing_args() {
-  match parse_success("a b c d:").run(&["a", "b", "c"]).unwrap_err() {
-    super::RunError::ArgumentCountMismatch{recipe, found, expected} => {
+  match parse_success("a b c d:").run(&BTreeMap::new(), &["a", "b", "c"]).unwrap_err() {
+    RunError::ArgumentCountMismatch{recipe, found, expected} => {
       assert_eq!(recipe, "a");
       assert_eq!(found, 2);
       assert_eq!(expected, 3);
@@ -788,8 +796,8 @@ fn missing_args() {
 
 #[test]
 fn missing_default() {
-  match parse_success("a b c d:\n echo {{b}}{{c}}{{d}}").run(&["a"]).unwrap_err() {
-    super::RunError::ArgumentCountMismatch{recipe, found, expected} => {
+  match parse_success("a b c d:\n echo {{b}}{{c}}{{d}}").run(&BTreeMap::new(), &["a"]).unwrap_err() {
+    RunError::ArgumentCountMismatch{recipe, found, expected} => {
       assert_eq!(recipe, "a");
       assert_eq!(found, 0);
       assert_eq!(expected, 3);
@@ -800,11 +808,25 @@ fn missing_default() {
 
 #[test]
 fn backtick_code() {
-  match parse_success("a:\n echo {{`function f { return 100; }; f`}}").run(&["a"]).unwrap_err() {
-    super::RunError::BacktickCode{code, token} => {
+  match parse_success("a:\n echo {{`function f { return 100; }; f`}}").run(&BTreeMap::new(), &["a"]).unwrap_err() {
+    RunError::BacktickCode{code, token} => {
       assert_eq!(code, 100);
       assert_eq!(token.lexeme, "`function f { return 100; }; f`");
     },
     other => panic!("expected an code run error, but got: {}", other),
   }
 }
+
+#[test]
+fn unknown_overrides() {
+  let mut overrides = BTreeMap::new();
+  overrides.insert("foo", "bar");
+  overrides.insert("baz", "bob");
+  match parse_success("a:\n echo {{`function f { return 100; }; f`}}")
+  .run(&overrides, &["a"]).unwrap_err() {
+    RunError::UnknownOverrides{overrides} => {
+      assert_eq!(overrides, &["baz", "foo"]);
+    },
+    other => panic!("expected an code run error, but got: {}", other),
+  }
+}