while loops

1 files changed, 53 insertions, 13 deletions

diff --git a/src/run/mod.rs b/src/run/mod.rs
index 106e22c..8c45548 100644
--- a/src/run/mod.rs
+++ b/src/run/mod.rs
@@ -103,6 +103,18 @@ enum SpawnedCmd {
     Pipeline(SpawnedPipeline),
 }
 
+trait IsSuccessful {
+    fn is_successful(&self) -> bool;
+}
+impl IsSuccessful for Result<(), ExecError> {
+    fn is_successful(&self) -> bool {
+        match self {
+            Ok(_) | Err(ExecError::ExecError(0)) => true,
+            _ => false,
+        }
+    }
+}
+
 impl SpawnedCmd {
     fn join(self) -> Result<(), ExecError> {
         match self {
@@ -244,12 +256,7 @@ impl Executor {
     ) -> SpawnedCmd {
         let mut this = self.clone();
         let handle = wait::spawn(move || -> Result<(), ExecError> {
-            for cmd in block.commands {
-                let cmd = cmd.expand(&mut this)?;
-                this.execute(cmd, stdin.try_clone()?, stdout.try_clone()?)
-                    .join()?;
-            }
-            Ok(())
+            this.execute_block_inner(&block, stdin, stdout)
         });
         SpawnedCmd::Fun(handle)
     }
@@ -320,6 +327,7 @@ impl Executor {
             Ast::VarAssign(va) => self.execute_var_assign(va),
             Ast::Pipes(pipes) => self.execute_pipeline(pipes, stdin, stdout),
             Ast::If(cond) => self.execute_if(cond, stdin, stdout),
+            Ast::While(w) => self.execute_while(w, stdin, stdout),
         }
     }
 
@@ -347,6 +355,20 @@ impl Executor {
         this.exec_loop(cmd, &mut [c1, c2])
     }
 
+    fn execute_block_inner(
+        &mut self,
+        block: &Block,
+        stdin: InputReader,
+        stdout: OutputWriter,
+    ) -> Result<(), ExecError> {
+        for cmd in block.commands.iter() {
+            let cmd = cmd.clone().expand(self)?;
+            self.execute(cmd, stdin.try_clone()?, stdout.try_clone()?)
+                .join()?;
+        }
+        Ok(())
+    }
+
     fn execute_if(
         &mut self,
         cond: parse::If<PostExpansion>,
@@ -358,14 +380,32 @@ impl Executor {
             let res = this
                 .execute_pipeline(cond.condition, stdin.try_clone()?, stdout.try_clone()?)
                 .join();
-            let block = match res {
-                Ok(_) | Err(ExecError::ExecError(0)) => cond.true_block,
-                Err(_) => cond.false_block,
+            let block = if res.is_successful() {
+                cond.true_block
+            } else {
+                cond.false_block
             };
-            for cmd in block.commands {
-                let cmd = cmd.expand(&mut this)?;
-                this.execute(cmd, stdin.try_clone()?, stdout.try_clone()?)
-                    .join()?;
+            this.execute_block_inner(&block, stdin.try_clone()?, stdout.try_clone()?)
+        });
+        SpawnedCmd::Fun(handle)
+    }
+
+    fn execute_while(
+        &mut self,
+        w: parse::While,
+        stdin: InputReader,
+        stdout: OutputWriter,
+    ) -> SpawnedCmd {
+        let mut this = self.clone();
+        let parse::While { condition, block } = w;
+        let handle = wait::spawn(move || -> Result<(), ExecError> {
+            while {
+                let condition = condition.clone().expand(&mut this)?;
+                this.execute_pipeline(condition, stdin.try_clone()?, stdout.try_clone()?)
+                    .join()
+                    .is_successful()
+            } {
+                this.execute_block_inner(&block, stdin.try_clone()?, stdout.try_clone()?)?;
             }
             Ok(())
         });