Remove snapcraft build and runtime support entirely

Snap was a best effort effort for Rustup, is currently broken, and we
have no capacity to develop it.

Remove it to signal clearly that issues with it are not something we're
focusing on - allowing other people to step up and maintain a
distribution of Rustup for Snap if desired.

Author: rbtcollins

.github/workflows/linux-builds-on-master.yaml

@@ -33,7 +33,8 @@ jobs:
           - target: armv7-unknown-linux-gnueabihf
             #snap_arch: armhf
     steps:
-      - uses: actions/checkout@v2
+      - name: Clone repo
+        uses: actions/checkout@v2
         with:
           # v2 defaults to a shallow checkout, but we need at least to the previous tag
           fetch-depth: 0
@@ -145,25 +146,6 @@ jobs:
           AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
           AWS_DEFAULT_REGION: us-west-1
         if: github.event_name == 'push' && github.ref == 'refs/heads/stable'
-      - name: Build a snapcraft configuration file
-        run: |
-          bash ci/snapcraft.bash
-        if: matrix.snap_arch != ''
-        env:
-          DO_SNAP: 1
-          SNAP_ARCH: ${{ matrix.snap_arch }}
-          SNAP_EDGE: 1 # skip-stable
-      - uses: snapcore/action-build@v1
-        id: snapcraftbuild
-        with:
-          path: snapcraft
-        if: matrix.snap_arch != ''
-      - uses: snapcore/action-publish@v1
-        with:
-          store_login: ${{ secrets.SNAPCRAFT_TOKEN }}
-          snap: ${{ steps.snapcraftbuild.outputs.snap }}
-          release: edge # skip-pr skip-stable
-        if: matrix.snap_arch != '' # skip-pr
       - name: Clear the cargo caches
         run: |
           cargo install cargo-cache --no-default-features --features ci-autoclean

.github/workflows/linux-builds-on-pr.yaml

@@ -26,7 +26,8 @@ jobs:
           - target: armv7-unknown-linux-gnueabihf
             #snap_arch: armhf
     steps:
-      - uses: actions/checkout@v2
+      - name: Clone repo
+        uses: actions/checkout@v2
         with:
           # v2 defaults to a shallow checkout, but we need at least to the previous tag
           fetch-depth: 0
@@ -138,24 +139,6 @@ jobs:
           AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
           AWS_DEFAULT_REGION: us-west-1
         if: github.event_name == 'push' && github.ref == 'refs/heads/stable'
-      - name: Build a snapcraft configuration file
-        run: |
-          bash ci/snapcraft.bash
-        if: matrix.snap_arch != ''
-        env:
-          DO_SNAP: 1
-          SNAP_ARCH: ${{ matrix.snap_arch }}
-          SNAP_EDGE: 1 # skip-stable
-      - uses: snapcore/action-build@v1
-        id: snapcraftbuild
-        with:
-          path: snapcraft
-        if: matrix.snap_arch != ''
-      - uses: snapcore/action-publish@v1
-        with:
-          store_login: ${{ secrets.SNAPCRAFT_TOKEN }}
-          snap: ${{ steps.snapcraftbuild.outputs.snap }}
-        if: matrix.snap_arch == 'not-for-prs' # skip-master skip-stable
       - name: Clear the cargo caches
         run: |
           cargo install cargo-cache --no-default-features --features ci-autoclean

.github/workflows/linux-builds-on-stable.yaml

@@ -56,7 +56,8 @@ jobs:
           - target: s390x-unknown-linux-gnu # skip-pr skip-master
             #snap_arch: s390x # skip-pr skip-master
     steps:
-      - uses: actions/checkout@v2
+      - name: Clone repo
+        uses: actions/checkout@v2
         with:
           # v2 defaults to a shallow checkout, but we need at least to the previous tag
           fetch-depth: 0
@@ -168,24 +169,6 @@ jobs:
           AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
           AWS_DEFAULT_REGION: us-west-1
         if: github.event_name == 'push' && github.ref == 'refs/heads/stable'
-      - name: Build a snapcraft configuration file
-        run: |
-          bash ci/snapcraft.bash
-        if: matrix.snap_arch != ''
-        env:
-          DO_SNAP: 1
-          SNAP_ARCH: ${{ matrix.snap_arch }}
-      - uses: snapcore/action-build@v1
-        id: snapcraftbuild
-        with:
-          path: snapcraft
-        if: matrix.snap_arch != ''
-      - uses: snapcore/action-publish@v1
-        with:
-          store_login: ${{ secrets.SNAPCRAFT_TOKEN }}
-          snap: ${{ steps.snapcraftbuild.outputs.snap }}
-          release: beta # skip-pr skip-master
-        if: matrix.snap_arch != '' # skip-pr
       - name: Clear the cargo caches
         run: |
           cargo install cargo-cache --no-default-features --features ci-autoclean

ci/actions-templates/linux-builds-template.yaml

@@ -64,7 +64,8 @@ jobs:
           - target: s390x-unknown-linux-gnu # skip-pr skip-master
             #snap_arch: s390x # skip-pr skip-master
     steps:
-      - uses: actions/checkout@v2
+      - name: Clone repo
+        uses: actions/checkout@v2
         with:
           # v2 defaults to a shallow checkout, but we need at least to the previous tag
           fetch-depth: 0
@@ -176,27 +177,6 @@ jobs:
           AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
           AWS_DEFAULT_REGION: us-west-1
         if: github.event_name == 'push' && github.ref == 'refs/heads/stable'
-      - name: Build a snapcraft configuration file
-        run: |
-          bash ci/snapcraft.bash
-        if: matrix.snap_arch != ''
-        env:
-          DO_SNAP: 1
-          SNAP_ARCH: ${{ matrix.snap_arch }}
-          SNAP_EDGE: 1 # skip-stable
-      - uses: snapcore/action-build@v1
-        id: snapcraftbuild
-        with:
-          path: snapcraft
-        if: matrix.snap_arch != ''
-      - uses: snapcore/action-publish@v1
-        with:
-          store_login: ${{ secrets.SNAPCRAFT_TOKEN }}
-          snap: ${{ steps.snapcraftbuild.outputs.snap }}
-          release: edge # skip-pr skip-stable
-          release: beta # skip-pr skip-master
-        if: matrix.snap_arch != '' # skip-pr
-        if: matrix.snap_arch == 'not-for-prs' # skip-master skip-stable
       - name: Clear the cargo caches
         run: |
           cargo install cargo-cache --no-default-features --features ci-autoclean

ci/snapcraft.bash

@@ -33,7 +33,7 @@ info: downloading self-updates
 If your `rustup` was built with the [no-self-update feature](https://github.com/rust-lang/rustup/blob/master/Cargo.toml#L25), it can not update
 itself. This is not the default, and only versions of `rustup` built with
 `--no-default-features`, or obtained from a third-party distributor who has
-disabled it (such as the Ubuntu snap store).
+disabled it (such as Nixos).
 
 Otherwise Rustup can update itself. It is possible to control Rustup's automatic
 self update mechanism with the `auto-self-update` configuration variable. This

doc/src/basics.md

@@ -292,23 +292,6 @@ pub(crate) fn self_update_permitted(explicit: bool) -> Result<SelfUpdatePermissi
         Ok(SelfUpdatePermission::Permit)
     } else {
         // Detect if rustup is not meant to self-update
-        match process().var("SNAP") {
-            Ok(_) => {
-                // We're running under snappy so don't even bother
-                // trying to self-update
-                // TODO: Report this to the user?
-                // TODO: Maybe ask snapd if there's an update and report
-                //       that to the user instead?
-                debug!("Skipping self-update because SNAP was detected");
-                if explicit {
-                    return Ok(SelfUpdatePermission::HardFail);
-                } else {
-                    return Ok(SelfUpdatePermission::Skip);
-                }
-            }
-            Err(env::VarError::NotPresent) => {}
-            Err(e) => return Err(e).context("Could not interrogate SNAP environment variable"),
-        }
         let current_exe = env::current_exe()?;
         let current_exe_dir = current_exe.parent().expect("Rustup isn't in a directory‽");
         if let Err(e) = tempfile::Builder::new()