Merge pull request #91 from github/cschleiden/improve-expression-validation

Validate expressions even when calling `fromJson`

actions-languageservice/src/validate.expressions.test.ts

@@ -359,7 +359,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: step a
-      env: 
+      env:
         step_env: job_a_env
       run: echo "hello \${{ env.step_env }}
 `;
@@ -376,7 +376,7 @@ env:
 jobs:
   a:
     runs-on: ubuntu-latest
-    env: 
+    env:
       envjoba: job_a_env
     steps:
     - name: step a
@@ -395,7 +395,7 @@ env:
 jobs:
   a:
     runs-on: ubuntu-latest
-    env: 
+    env:
       envjoba: job_a_env
     steps:
     - name: step a
@@ -1185,6 +1185,9 @@ jobs:
     - run: echo "hello \${{ github.event.inputs.name }}"
     - run: echo "hello \${{ github.event.inputs.third-name }}"
     - run: echo "hello \${{ github.event.inputs.random }}"
+    - run: echo \${{ fromJSON(inputs.random2) }}
+    - run: echo "hello \${{ inputs.random }}"
+      name: "\${{ fromJSON('test') == inputs.name }}"
 `;
       const result = await validate(createDocument("wf.yaml", input));
 
@@ -1202,6 +1205,34 @@ jobs:
             }
           },
           severity: DiagnosticSeverity.Warning
+        },
+        {
+          message: "Context access might be invalid: random2",
+          range: {
+            end: {
+              character: 47,
+              line: 20
+            },
+            start: {
+              character: 16,
+              line: 20
+            }
+          },
+          severity: 2
+        },
+        {
+          message: "Context access might be invalid: random",
+          range: {
+            end: {
+              character: 43,
+              line: 21
+            },
+            start: {
+              character: 23,
+              line: 21
+            }
+          },
+          severity: 2
         }
       ]);
     });

actions-languageservice/src/validate.ts

@@ -1,4 +1,11 @@
-import {Evaluator, Lexer, Parser} from "@github/actions-expressions";
+import {
+  data,
+  Evaluator,
+  ExpressionEvaluationError,
+  Lexer,
+  Parser,
+  wellKnownFunctions
+} from "@github/actions-expressions";
 import {Expr} from "@github/actions-expressions/ast";
 import {
   convertWorkflowTemplate,
@@ -202,7 +209,7 @@ async function validateExpression(
     try {
       const context = await getContext(namedContexts, contextProviderConfig, workflowContext, Mode.Validation);
 
-      const e = new Evaluator(expr, wrapDictionary(context));
+      const e = new Evaluator(expr, wrapDictionary(context), validatorFunctions);
       e.evaluate();
 
       // Any invalid context access would've thrown an error via the `ErrorDictionary`, for now we don't have to check the actual
@@ -214,7 +221,25 @@ async function validateExpression(
           severity: DiagnosticSeverity.Warning,
           range: mapRange(expression.range)
         });
+      } else if (e instanceof ExpressionEvaluationError) {
+        diagnostics.push({
+          message: `Expression might be invalid: ${e.message}`,
+          severity: DiagnosticSeverity.Error,
+          range: mapRange(expression.range)
+        });
       }
     }
   }
 }
+
+// Custom implementations for standard actions-expression functions used during validation. For example,
+// for fromJson we'll most likely not have a valid input. In order to not throw, we'll always return an
+// empty dictionary.
+const validatorFunctions = new Map(
+  Object.entries({
+    fromjson: {
+      ...wellKnownFunctions.fromjson,
+      call: () => new data.Dictionary()
+    }
+  })
+);