chore(turborepo): Improve pipeline error message (#8231)

### Description

Made a nicer error message for having a `pipeline` key instead of
`tasks`.

### Testing Instructions

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  Give a quick description of steps to test your changes.
-->

---------

Co-authored-by: Anthony Shew <[email protected]>

crates/turborepo-lib/src/config.rs

@@ -132,6 +132,14 @@ pub enum Error {
         #[source_code]
         text: NamedSource,
     },
+    #[error("found `pipeline` field instead of `tasks`")]
+    #[diagnostic(help("Deprecated in 2.0: `pipeline` has been renamed to `tasks`"))]
+    PipelineField {
+        #[label("rename `pipeline` field to `tasks`")]
+        span: Option<SourceSpan>,
+        #[source_code]
+        text: NamedSource,
+    },
     #[error("Failed to create APIClient: {0}")]
     ApiClient(#[source] turborepo_api_client::Error),
     #[error("{0} is not UTF8.")]

crates/turborepo-lib/src/turbo_json/mod.rs

@@ -117,6 +117,9 @@ pub struct RawTurboJson {
     // and cache behavior on a per task or per package-task basis.
     #[serde(skip_serializing_if = "Option::is_none")]
     pub tasks: Option<Pipeline>,
+
+    #[serde(skip_serializing)]
+    pub pipeline: Option<Spanned<Pipeline>>,
     // Configuration options when interfacing with the remote cache
     #[serde(skip_serializing_if = "Option::is_none")]
     pub(crate) remote_cache: Option<RawRemoteCacheOptions>,
@@ -432,6 +435,10 @@ impl TryFrom<RawTurboJson> for TurboJson {
     type Error = Error;
 
     fn try_from(raw_turbo: RawTurboJson) -> Result<Self, Error> {
+        if let Some(pipeline) = raw_turbo.pipeline {
+            let (span, text) = pipeline.span_and_text("turbo.json");
+            return Err(Error::PipelineField { span, text });
+        }
         let mut global_env = HashSet::new();
         let mut global_file_dependencies = HashSet::new();
 

crates/turborepo-lib/src/turbo_json/parser.rs

@@ -147,7 +147,8 @@ impl WithMetadata for RawTurboJson {
         self.global_dependencies.add_text(text.clone());
         self.global_env.add_text(text.clone());
         self.global_pass_through_env.add_text(text.clone());
-        self.tasks.add_text(text);
+        self.tasks.add_text(text.clone());
+        self.pipeline.add_text(text);
     }
 
     fn add_path(&mut self, path: Arc<str>) {
@@ -156,7 +157,8 @@ impl WithMetadata for RawTurboJson {
         self.global_dependencies.add_path(path.clone());
         self.global_env.add_path(path.clone());
         self.global_pass_through_env.add_path(path.clone());
-        self.tasks.add_path(path);
+        self.tasks.add_path(path.clone());
+        self.pipeline.add_path(path);
     }
 }