Remove support for the version attribute

First added in #161 this never ended up panning out, so let's remove the
experimental suport which isn't actually used by anything today and hold off on
any other changes until an RFC happens.

crates/cli-support/src/js/mod.rs

@@ -5,7 +5,6 @@ use std::mem;
 use failure::{Error, ResultExt};
 use parity_wasm;
 use parity_wasm::elements::*;
-use serde_json;
 use shared;
 use wasm_gc;
 
@@ -43,7 +42,6 @@ pub struct Context<'a> {
     pub exported_classes: HashMap<String, ExportedClass>,
     pub function_table_needed: bool,
     pub run_descriptor: &'a Fn(&str) -> Option<Vec<u32>>,
-    pub module_versions: Vec<(String, String)>,
 }
 
 #[derive(Default)]
@@ -458,7 +456,6 @@ impl<'a> Context<'a> {
 
         self.export_table();
         self.gc()?;
-        self.add_wasm_pack_section();
 
         while js.contains("\n\n\n") {
             js = js.replace("\n\n\n", "\n\n");
@@ -1629,28 +1626,6 @@ impl<'a> Context<'a> {
         self.globals.push_str("\n");
     }
 
-    fn add_wasm_pack_section(&mut self) {
-        if self.module_versions.len() == 0 {
-            return;
-        }
-
-        #[derive(Serialize)]
-        struct WasmPackSchema<'a> {
-            version: &'a str,
-            modules: &'a [(String, String)],
-        }
-
-        let contents = serde_json::to_string(&WasmPackSchema {
-            version: "0.0.1",
-            modules: &self.module_versions,
-        }).unwrap();
-
-        let mut section = CustomSection::default();
-        *section.name_mut() = "__wasm_pack_unstable".to_string();
-        *section.payload_mut() = contents.into_bytes();
-        self.module.sections_mut().push(Section::Custom(section));
-    }
-
     fn use_node_require(&self) -> bool {
         self.config.nodejs && !self.config.nodejs_experimental_modules
     }
@@ -1766,7 +1741,6 @@ impl<'a, 'b> SubContext<'a, 'b> {
     }
 
     fn generate_import(&mut self, import: &shared::Import) -> Result<(), Error> {
-        self.validate_import_module(import)?;
         match import.kind {
             shared::ImportKind::Function(ref f) => {
                 self.generate_import_function(import, f).with_context(|_| {
@@ -1787,41 +1761,6 @@ impl<'a, 'b> SubContext<'a, 'b> {
         Ok(())
     }
 
-    fn validate_import_module(&mut self, import: &shared::Import) -> Result<(), Error> {
-        let version = match import.version {
-            Some(ref s) => s,
-            None => return Ok(()),
-        };
-        let module = match import.module {
-            Some(ref s) => s,
-            None => return Ok(()),
-        };
-        if module.starts_with("./") {
-            return Ok(());
-        }
-        let pkg = if module.starts_with("@") {
-            // Translate `@foo/bar/baz` to `@foo/bar` and `@foo/bar` to itself
-            let first_slash = match module.find('/') {
-                Some(i) => i,
-                None => bail!(
-                    "packages starting with `@` must be of the form \
-                     `@foo/bar`, but found: `{}`",
-                    module
-                ),
-            };
-            match module[first_slash + 1..].find('/') {
-                Some(i) => &module[..i],
-                None => module,
-            }
-        } else {
-            module.split('/').next().unwrap()
-        };
-        self.cx
-            .module_versions
-            .push((pkg.to_string(), version.clone()));
-        Ok(())
-    }
-
     fn generate_import_static(
         &mut self,
         info: &shared::Import,