Mandats : origin→FK identité + nomination auto + boutons + tests intégration

- origin TEXT → origin_id UUID FK duniter_identities (migration e3f4a5b6c7d8)
- GET /auth/identities?q= : recherche d'identités par nom/adresse
- MandateCreate.nomination_mode : auto (auto-assign auteur), collective, postpone
- Wizard new.vue : champ origine = picker identité, checkbox "Démarrer maintenant"
- [id].vue : modal "Assigner" = search-picker (résout UUID vs adresse SS58), affiche
  origin_display_name + mandatee_display_name, inputs natifs (<input>/<textarea>)
- Erreurs API visibles dans l'UI (plus de catch silencieux)
- test_mandate_flows.py : 17 tests intégration SQLite réels (origin, nomination,
  assign, lifecycle, revocation, interactions croisées) — 241 tests total OK

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/alembic/versions/2026_04_25_1000-e3f4a5b6c7d8_mandate_origin_id.py

@@ -0,0 +1,27 @@
+"""Mandate origin: replace free-text with FK to duniter_identities.
+
+Revision ID: e3f4a5b6c7d8
+Revises: d91a3c7f8b02
+Create Date: 2026-04-25 10:00:00.000000
+"""
+
+from __future__ import annotations
+
+from alembic import op
+
+revision = "e3f4a5b6c7d8"
+down_revision = "d91a3c7f8b02"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.execute("ALTER TABLE mandates DROP COLUMN IF EXISTS origin")
+    op.execute("ALTER TABLE mandates ADD COLUMN IF NOT EXISTS origin_id UUID REFERENCES duniter_identities(id)")
+    op.execute("CREATE INDEX IF NOT EXISTS ix_mandates_origin_id ON mandates (origin_id)")
+
+
+def downgrade() -> None:
+    op.execute("DROP INDEX IF EXISTS ix_mandates_origin_id")
+    op.execute("ALTER TABLE mandates DROP COLUMN IF EXISTS origin_id")
+    op.execute("ALTER TABLE mandates ADD COLUMN IF NOT EXISTS origin TEXT")

backend/app/models/mandate.py

@@ -12,10 +12,10 @@ class Mandate(Base):
 
     id: Mapped[uuid.UUID] = mapped_column(Uuid, primary_key=True, default=uuid.uuid4)
     title: Mapped[str] = mapped_column(String(256), nullable=False)
-    origin: Mapped[str | None] = mapped_column(Text)           # contexte / déclencheur du mandat
+    origin_id: Mapped[uuid.UUID | None] = mapped_column(ForeignKey("duniter_identities.id"), nullable=True, index=True)
     description: Mapped[str | None] = mapped_column(Text)
-    mandate_type: Mapped[str] = mapped_column(String(64), nullable=False)  # techcomm, smith, custom
-    status: Mapped[str] = mapped_column(String(32), default="draft")  # draft, candidacy, voting, active, reporting, completed, revoked
+    mandate_type: Mapped[str] = mapped_column(String(64), nullable=False)
+    status: Mapped[str] = mapped_column(String(32), default="draft")
     organization_id: Mapped[uuid.UUID | None] = mapped_column(ForeignKey("organizations.id"), nullable=True, index=True)
     mandatee_id: Mapped[uuid.UUID | None] = mapped_column(ForeignKey("duniter_identities.id"))
     decision_id: Mapped[uuid.UUID | None] = mapped_column(ForeignKey("decisions.id"))
@@ -24,7 +24,27 @@ class Mandate(Base):
     created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())
     updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())
 
-    steps: Mapped[list["MandateStep"]] = relationship(back_populates="mandate", cascade="all, delete-orphan", order_by="MandateStep.step_order")
+    steps: Mapped[list["MandateStep"]] = relationship(
+        back_populates="mandate", cascade="all, delete-orphan", order_by="MandateStep.step_order"
+    )
+    origin_identity: Mapped["DuniterIdentity | None"] = relationship(  # type: ignore[name-defined]
+        "DuniterIdentity", foreign_keys=[origin_id]
+    )
+    mandatee: Mapped["DuniterIdentity | None"] = relationship(  # type: ignore[name-defined]
+        "DuniterIdentity", foreign_keys=[mandatee_id]
+    )
+
+    @property
+    def origin_display_name(self) -> str | None:
+        if self.origin_identity is not None:
+            return self.origin_identity.display_name or self.origin_identity.address
+        return None
+
+    @property
+    def mandatee_display_name(self) -> str | None:
+        if self.mandatee is not None:
+            return self.mandatee.display_name or self.mandatee.address
+        return None
 
 
 class MandateStep(Base):
@@ -33,12 +53,16 @@ class MandateStep(Base):
     id: Mapped[uuid.UUID] = mapped_column(Uuid, primary_key=True, default=uuid.uuid4)
     mandate_id: Mapped[uuid.UUID] = mapped_column(ForeignKey("mandates.id"), nullable=False)
     step_order: Mapped[int] = mapped_column(Integer, nullable=False)
-    step_type: Mapped[str] = mapped_column(String(32), nullable=False)  # formulation, candidacy, vote, assignment, reporting, completion, revocation
+    step_type: Mapped[str] = mapped_column(String(32), nullable=False)
     title: Mapped[str | None] = mapped_column(String(256))
     description: Mapped[str | None] = mapped_column(Text)
-    status: Mapped[str] = mapped_column(String(32), default="pending")  # pending, active, completed, skipped
+    status: Mapped[str] = mapped_column(String(32), default="pending")
     vote_session_id: Mapped[uuid.UUID | None] = mapped_column(ForeignKey("vote_sessions.id"))
     outcome: Mapped[str | None] = mapped_column(Text)
     created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())
 
     mandate: Mapped["Mandate"] = relationship(back_populates="steps")
+
+
+# Avoid circular import — DuniterIdentity imported at runtime by SQLAlchemy relationship resolution
+from app.models.user import DuniterIdentity  # noqa: E402, F401

backend/app/routers/auth.py

@@ -5,7 +5,8 @@ from __future__ import annotations
 import secrets
 from datetime import datetime, timedelta, timezone
 
-from fastapi import APIRouter, Depends, HTTPException, Response, status
+from fastapi import APIRouter, Depends, HTTPException, Query, Response, status
+from sqlalchemy import or_, select
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.config import settings
@@ -232,3 +233,24 @@ async def logout(
     for session in sessions:
         await db.delete(session)
     await db.commit()
+
+
+@router.get("/identities", response_model=list[IdentityOut])
+async def search_identities(
+    q: str = Query(..., min_length=1, description="Recherche par adresse ou nom"),
+    limit: int = Query(default=10, ge=1, le=50),
+    db: AsyncSession = Depends(get_db),
+) -> list[IdentityOut]:
+    """Search Duniter identities by address prefix or display_name."""
+    result = await db.execute(
+        select(DuniterIdentity)
+        .where(
+            or_(
+                DuniterIdentity.address.ilike(f"{q}%"),
+                DuniterIdentity.display_name.ilike(f"%{q}%"),
+            )
+        )
+        .order_by(DuniterIdentity.display_name)
+        .limit(limit)
+    )
+    return [IdentityOut.model_validate(i) for i in result.scalars().all()]

backend/app/routers/mandates.py

@@ -38,10 +38,13 @@ router = APIRouter()
 
 
 async def _get_mandate(db: AsyncSession, mandate_id: uuid.UUID) -> Mandate:
-    """Fetch a mandate by ID with its steps eagerly loaded, or raise 404."""
     result = await db.execute(
         select(Mandate)
-        .options(selectinload(Mandate.steps))
+        .options(
+            selectinload(Mandate.steps),
+            selectinload(Mandate.origin_identity),
+            selectinload(Mandate.mandatee),
+        )
         .where(Mandate.id == mandate_id)
     )
     mandate = result.scalar_one_or_none()
@@ -50,6 +53,13 @@ async def _get_mandate(db: AsyncSession, mandate_id: uuid.UUID) -> Mandate:
     return mandate
 
 
+def _mandate_out(mandate: Mandate) -> MandateOut:
+    out = MandateOut.model_validate(mandate)
+    out.origin_display_name = mandate.origin_display_name
+    out.mandatee_display_name = mandate.mandatee_display_name
+    return out
+
+
 # ── Mandate routes ──────────────────────────────────────────────────────────
 
 
@@ -57,13 +67,16 @@ async def _get_mandate(db: AsyncSession, mandate_id: uuid.UUID) -> Mandate:
 async def list_mandates(
     db: AsyncSession = Depends(get_db),
     org_id: uuid.UUID | None = Depends(get_active_org_id),
-    mandate_type: str | None = Query(default=None, description="Filtrer par type de mandat"),
-    status_filter: str | None = Query(default=None, alias="status", description="Filtrer par statut"),
+    mandate_type: str | None = Query(default=None),
+    status_filter: str | None = Query(default=None, alias="status"),
     skip: int = Query(default=0, ge=0),
     limit: int = Query(default=50, ge=1, le=200),
 ) -> list[MandateOut]:
-    """List all mandates with optional filters."""
-    stmt = select(Mandate).options(selectinload(Mandate.steps))
+    stmt = select(Mandate).options(
+        selectinload(Mandate.steps),
+        selectinload(Mandate.origin_identity),
+        selectinload(Mandate.mandatee),
+    )
 
     if org_id is not None:
         stmt = stmt.where(Mandate.organization_id == org_id)
@@ -76,7 +89,7 @@ async def list_mandates(
     result = await db.execute(stmt)
     mandates = result.scalars().unique().all()
 
-    return [MandateOut.model_validate(m) for m in mandates]
+    return [_mandate_out(m) for m in mandates]
 
 
 @router.post("/", response_model=MandateOut, status_code=status.HTTP_201_CREATED)
@@ -86,15 +99,20 @@ async def create_mandate(
     identity: DuniterIdentity = Depends(get_current_identity),
     org_id: uuid.UUID | None = Depends(get_active_org_id),
 ) -> MandateOut:
-    """Create a new mandate."""
-    mandate = Mandate(**payload.model_dump(), organization_id=org_id)
+    data = payload.model_dump()
+    nomination_mode = data.pop("nomination_mode", "postpone")
+
+    mandate = Mandate(**data, organization_id=org_id)
+
+    if nomination_mode == "auto":
+        mandate.mandatee_id = identity.id
+
     db.add(mandate)
     await db.commit()
     await db.refresh(mandate)
 
-    # Reload with steps (empty at creation)
     mandate = await _get_mandate(db, mandate.id)
-    return MandateOut.model_validate(mandate)
+    return _mandate_out(mandate)
 
 
 @router.get("/{id}", response_model=MandateOut)
@@ -102,9 +120,8 @@ async def get_mandate(
     id: uuid.UUID,
     db: AsyncSession = Depends(get_db),
 ) -> MandateOut:
-    """Get a single mandate with all its steps."""
     mandate = await _get_mandate(db, id)
-    return MandateOut.model_validate(mandate)
+    return _mandate_out(mandate)
 
 
 @router.put("/{id}", response_model=MandateOut)
@@ -114,19 +131,14 @@ async def update_mandate(
     db: AsyncSession = Depends(get_db),
     identity: DuniterIdentity = Depends(get_current_identity),
 ) -> MandateOut:
-    """Update a mandate's metadata."""
     mandate = await _get_mandate(db, id)
 
-    update_data = payload.model_dump(exclude_unset=True)
-    for field, value in update_data.items():
+    for field, value in payload.model_dump(exclude_unset=True).items():
         setattr(mandate, field, value)
 
     await db.commit()
-    await db.refresh(mandate)
-
-    # Reload with steps
     mandate = await _get_mandate(db, mandate.id)
-    return MandateOut.model_validate(mandate)
+    return _mandate_out(mandate)
 
 
 @router.delete("/{id}", status_code=status.HTTP_204_NO_CONTENT, response_class=Response, response_model=None)
@@ -135,7 +147,6 @@ async def delete_mandate(
     db: AsyncSession = Depends(get_db),
     identity: DuniterIdentity = Depends(get_current_identity),
 ) -> None:
-    """Delete a mandate (only if in draft status)."""
     mandate = await _get_mandate(db, id)
 
     if mandate.status != "draft":
@@ -158,13 +169,9 @@ async def add_step(
     db: AsyncSession = Depends(get_db),
     identity: DuniterIdentity = Depends(get_current_identity),
 ) -> MandateStepOut:
-    """Add a step to a mandate process."""
     mandate = await _get_mandate(db, id)
 
-    step = MandateStep(
-        mandate_id=mandate.id,
-        **payload.model_dump(),
-    )
+    step = MandateStep(mandate_id=mandate.id, **payload.model_dump())
     db.add(step)
     await db.commit()
     await db.refresh(step)
@@ -177,7 +184,6 @@ async def list_steps(
     id: uuid.UUID,
     db: AsyncSession = Depends(get_db),
 ) -> list[MandateStepOut]:
-    """List all steps for a mandate, ordered by step_order."""
     mandate = await _get_mandate(db, id)
     return [MandateStepOut.model_validate(s) for s in mandate.steps]
 
@@ -191,17 +197,17 @@ async def advance_mandate_endpoint(
     db: AsyncSession = Depends(get_db),
     identity: DuniterIdentity = Depends(get_current_identity),
 ) -> MandateAdvanceOut:
-    """Advance a mandate to its next step or status."""
     try:
         mandate = await advance_mandate(id, db)
     except ValueError as exc:
         raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(exc))
 
-    # Reload with steps for complete output
     mandate = await _get_mandate(db, mandate.id)
-    data = MandateOut.model_validate(mandate).model_dump()
-    data["message"] = f"Mandat avance au statut : {mandate.status}"
-    return MandateAdvanceOut(**data)
+    out = _mandate_out(mandate)
+    return MandateAdvanceOut(
+        **out.model_dump(),
+        message=f"Mandat avance au statut : {mandate.status}",
+    )
 
 
 @router.post("/{id}/assign", response_model=MandateOut)
@@ -211,15 +217,13 @@ async def assign_mandatee_endpoint(
     db: AsyncSession = Depends(get_db),
     identity: DuniterIdentity = Depends(get_current_identity),
 ) -> MandateOut:
-    """Assign a mandatee to a mandate."""
     try:
         mandate = await assign_mandatee(id, payload.mandatee_id, db)
     except ValueError as exc:
         raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(exc))
 
-    # Reload with steps
     mandate = await _get_mandate(db, mandate.id)
-    return MandateOut.model_validate(mandate)
+    return _mandate_out(mandate)
 
 
 @router.post("/{id}/revoke", response_model=MandateOut)
@@ -228,15 +232,13 @@ async def revoke_mandate_endpoint(
     db: AsyncSession = Depends(get_db),
     identity: DuniterIdentity = Depends(get_current_identity),
 ) -> MandateOut:
-    """Revoke an active mandate."""
     try:
         mandate = await revoke_mandate(id, db)
     except ValueError as exc:
         raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(exc))
 
-    # Reload with steps
     mandate = await _get_mandate(db, mandate.id)
-    return MandateOut.model_validate(mandate)
+    return _mandate_out(mandate)
 
 
 @router.post(
@@ -250,7 +252,6 @@ async def create_vote_session_for_step_endpoint(
     db: AsyncSession = Depends(get_db),
     identity: DuniterIdentity = Depends(get_current_identity),
 ) -> VoteSessionOut:
-    """Create a vote session linked to a mandate step."""
     try:
         session = await create_vote_session_for_step(id, step_id, db)
     except ValueError as exc:

backend/app/schemas/mandate.py

@@ -10,21 +10,13 @@ from pydantic import BaseModel, ConfigDict, Field
 
 
 class MandateStepCreate(BaseModel):
-    """Payload for creating a step within a mandate process."""
-
     step_order: int = Field(..., ge=0)
-    step_type: str = Field(
-        ...,
-        max_length=32,
-        description="formulation, candidacy, vote, assignment, reporting, completion, revocation",
-    )
+    step_type: str = Field(..., max_length=32)
     title: str | None = Field(default=None, max_length=256)
     description: str | None = None
 
 
 class MandateStepOut(BaseModel):
-    """Full mandate step representation."""
-
     model_config = ConfigDict(from_attributes=True)
 
     id: UUID
@@ -43,44 +35,45 @@ class MandateStepOut(BaseModel):
 
 
 class MandateCreate(BaseModel):
-    """Payload for creating a new mandate."""
-
     title: str = Field(..., min_length=1, max_length=256)
-    origin: str | None = None
+    origin_id: UUID | None = None
     description: str | None = None
-    mandate_type: str = Field(..., max_length=64, description="techcomm, smith, custom")
+    mandate_type: str = Field(..., max_length=64)
+    nomination_mode: str = Field(
+        default="postpone",
+        description="auto (auto-assign author), collective, postpone",
+    )
     decision_id: UUID | None = None
     starts_at: datetime | None = None
     ends_at: datetime | None = None
 
 
 class MandateUpdate(BaseModel):
-    """Partial update for a mandate."""
-
     title: str | None = Field(default=None, max_length=256)
+    origin_id: UUID | None = None
     description: str | None = None
     mandate_type: str | None = Field(default=None, max_length=64)
     decision_id: UUID | None = None
+    starts_at: datetime | None = None
+    ends_at: datetime | None = None
 
 
 class MandateAssignRequest(BaseModel):
-    """Request body for assigning a mandatee to a mandate."""
-
-    mandatee_id: UUID = Field(..., description="ID de l'identite Duniter du mandataire")
+    mandatee_id: UUID = Field(..., description="UUID de l'identite Duniter du mandataire")
 
 
 class MandateOut(BaseModel):
-    """Full mandate representation returned by the API."""
-
     model_config = ConfigDict(from_attributes=True)
 
     id: UUID
     title: str
-    origin: str | None = None
+    origin_id: UUID | None = None
+    origin_display_name: str | None = None
     description: str | None = None
     mandate_type: str
     status: str
     mandatee_id: UUID | None = None
+    mandatee_display_name: str | None = None
     decision_id: UUID | None = None
     starts_at: datetime | None = None
     ends_at: datetime | None = None
@@ -89,22 +82,5 @@ class MandateOut(BaseModel):
     steps: list[MandateStepOut] = Field(default_factory=list)
 
 
-class MandateAdvanceOut(BaseModel):
-    """Output after advancing a mandate through its workflow."""
-
-    model_config = ConfigDict(from_attributes=True)
-
-    id: UUID
-    title: str
-    origin: str | None = None
-    description: str | None = None
-    mandate_type: str
-    status: str
-    mandatee_id: UUID | None = None
-    decision_id: UUID | None = None
-    starts_at: datetime | None = None
-    ends_at: datetime | None = None
-    created_at: datetime
-    updated_at: datetime
-    steps: list[MandateStepOut] = Field(default_factory=list)
+class MandateAdvanceOut(MandateOut):
     message: str = Field(..., description="Message decrivant l'avancement effectue")

backend/app/tests/test_mandate_flows.py

@@ -0,0 +1,405 @@
+"""Integration tests for mandate flows: nomination, lifecycle, assignment, revocation.
+
+Uses a real in-memory SQLite database — no mocks of the DB layer.
+Tests the service functions directly to verify interconnected business logic.
+"""
+
+from __future__ import annotations
+
+import uuid
+from datetime import datetime, timezone
+
+import pytest
+import pytest_asyncio
+from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
+from sqlalchemy.orm import selectinload
+from sqlalchemy import select
+
+import app.models  # noqa: F401 — registers all models with Base.metadata
+from app.database import Base
+from app.models.mandate import Mandate, MandateStep
+from app.models.user import DuniterIdentity
+from app.services.mandate_service import (
+    advance_mandate,
+    assign_mandatee,
+    revoke_mandate,
+)
+
+
+# ---------------------------------------------------------------------------
+# Fixtures
+# ---------------------------------------------------------------------------
+
+
+@pytest_asyncio.fixture
+async def engine():
+    eng = create_async_engine("sqlite+aiosqlite:///:memory:", echo=False)
+    async with eng.begin() as conn:
+        await conn.run_sync(Base.metadata.create_all)
+    yield eng
+    await eng.dispose()
+
+
+@pytest_asyncio.fixture
+async def db(engine):
+    factory = async_sessionmaker(engine, class_=AsyncSession, expire_on_commit=False)
+    async with factory() as session:
+        yield session
+
+
+async def _mk_identity(db: AsyncSession, display_name: str = "Alice") -> DuniterIdentity:
+    ident = DuniterIdentity(
+        id=uuid.uuid4(),
+        address=f"5{uuid.uuid4().hex[:46]}",
+        display_name=display_name,
+        wot_status="member",
+        is_smith=False,
+        is_techcomm=False,
+    )
+    db.add(ident)
+    await db.commit()
+    await db.refresh(ident)
+    return ident
+
+
+async def _mk_mandate(
+    db: AsyncSession,
+    *,
+    mandatee_id: uuid.UUID | None = None,
+    origin_id: uuid.UUID | None = None,
+    status: str = "draft",
+    steps: list[dict] | None = None,
+) -> Mandate:
+    mandate = Mandate(
+        id=uuid.uuid4(),
+        title="Mandat test",
+        mandate_type="functional",
+        status=status,
+        mandatee_id=mandatee_id,
+        origin_id=origin_id,
+    )
+    db.add(mandate)
+    await db.flush()
+
+    for i, s in enumerate(steps or []):
+        step = MandateStep(
+            id=uuid.uuid4(),
+            mandate_id=mandate.id,
+            step_order=i,
+            step_type=s.get("step_type", "formulation"),
+            title=s.get("title"),
+            status=s.get("status", "pending"),
+        )
+        db.add(step)
+
+    await db.commit()
+    await db.refresh(mandate)
+    return mandate
+
+
+async def _reload(db: AsyncSession, mandate_id: uuid.UUID) -> Mandate:
+    result = await db.execute(
+        select(Mandate)
+        .options(
+            selectinload(Mandate.steps),
+            selectinload(Mandate.origin_identity),
+            selectinload(Mandate.mandatee),
+        )
+        .where(Mandate.id == mandate_id)
+    )
+    return result.scalar_one()
+
+
+# ---------------------------------------------------------------------------
+# TestMandateOrigin
+# ---------------------------------------------------------------------------
+
+
+class TestMandateOrigin:
+    """origin_id must link to a real DuniterIdentity and expose display_name."""
+
+    @pytest.mark.asyncio
+    async def test_origin_id_linked(self, db: AsyncSession):
+        author = await _mk_identity(db, "Baptiste")
+        mandate = await _mk_mandate(db, origin_id=author.id)
+
+        loaded = await _reload(db, mandate.id)
+
+        assert loaded.origin_id == author.id
+        assert loaded.origin_display_name == "Baptiste"
+
+    @pytest.mark.asyncio
+    async def test_origin_id_optional(self, db: AsyncSession):
+        mandate = await _mk_mandate(db)
+
+        loaded = await _reload(db, mandate.id)
+
+        assert loaded.origin_id is None
+        assert loaded.origin_display_name is None
+
+
+# ---------------------------------------------------------------------------
+# TestAutoNomination
+# ---------------------------------------------------------------------------
+
+
+class TestAutoNomination:
+    """Auto-désignation: mandatee = author, no candidacy steps needed."""
+
+    @pytest.mark.asyncio
+    async def test_auto_assign_author(self, db: AsyncSession):
+        author = await _mk_identity(db, "Constance")
+        mandate = await _mk_mandate(db, mandatee_id=author.id)
+
+        loaded = await _reload(db, mandate.id)
+
+        assert loaded.mandatee_id == author.id
+        assert loaded.mandatee_display_name == "Constance"
+
+    @pytest.mark.asyncio
+    async def test_auto_assign_then_advance_to_active(self, db: AsyncSession):
+        author = await _mk_identity(db, "David")
+        mandate = await _mk_mandate(
+            db,
+            mandatee_id=author.id,
+            steps=[
+                {"step_type": "formulation", "status": "pending"},
+                {"step_type": "assignment", "status": "pending"},
+                {"step_type": "reporting", "status": "pending"},
+            ],
+        )
+
+        # First advance: draft → candidacy, activates step 0
+        result = await advance_mandate(mandate.id, db)
+        assert result.status == "candidacy"
+
+        loaded = await _reload(db, mandate.id)
+        assert loaded.steps[0].status == "active"
+        assert loaded.steps[1].status == "pending"
+
+        # Second advance: step 0 → completed, step 1 → active
+        await advance_mandate(mandate.id, db)
+        loaded = await _reload(db, mandate.id)
+        assert loaded.steps[0].status == "completed"
+        assert loaded.steps[1].status == "active"
+
+
+# ---------------------------------------------------------------------------
+# TestMandateAssign
+# ---------------------------------------------------------------------------
+
+
+class TestMandateAssign:
+    """assign_mandatee service: proper UUID lookup, display_name populated."""
+
+    @pytest.mark.asyncio
+    async def test_assign_sets_mandatee_and_starts_at(self, db: AsyncSession):
+        identity = await _mk_identity(db, "Elodie")
+        mandate = await _mk_mandate(db, status="active")
+
+        await assign_mandatee(mandate.id, identity.id, db)
+
+        loaded = await _reload(db, mandate.id)
+        assert loaded.mandatee_id == identity.id
+        assert loaded.starts_at is not None
+        assert loaded.mandatee_display_name == "Elodie"
+
+    @pytest.mark.asyncio
+    async def test_assign_unknown_identity_raises(self, db: AsyncSession):
+        mandate = await _mk_mandate(db, status="active")
+
+        with pytest.raises(ValueError, match="Identite Duniter introuvable"):
+            await assign_mandatee(mandate.id, uuid.uuid4(), db)
+
+    @pytest.mark.asyncio
+    async def test_assign_completed_mandate_raises(self, db: AsyncSession):
+        identity = await _mk_identity(db, "Fabien")
+        mandate = await _mk_mandate(db, status="completed")
+
+        with pytest.raises(ValueError, match="statut terminal"):
+            await assign_mandatee(mandate.id, identity.id, db)
+
+    @pytest.mark.asyncio
+    async def test_reassign_replaces_mandatee(self, db: AsyncSession):
+        first = await _mk_identity(db, "Gilles")
+        second = await _mk_identity(db, "Hélène")
+        mandate = await _mk_mandate(db, mandatee_id=first.id, status="active")
+
+        await assign_mandatee(mandate.id, second.id, db)
+
+        loaded = await _reload(db, mandate.id)
+        assert loaded.mandatee_id == second.id
+
+
+# ---------------------------------------------------------------------------
+# TestMandateLifecycle
+# ---------------------------------------------------------------------------
+
+
+class TestMandateLifecycle:
+    """advance_mandate: full lifecycle with and without steps."""
+
+    @pytest.mark.asyncio
+    async def test_full_lifecycle_no_steps(self, db: AsyncSession):
+        mandate = await _mk_mandate(db)
+        statuses = [mandate.status]
+
+        for _ in range(10):
+            m = await advance_mandate(mandate.id, db)
+            statuses.append(m.status)
+            if m.status == "completed":
+                break
+
+        assert statuses == ["draft", "candidacy", "voting", "active", "reporting", "completed"]
+
+    @pytest.mark.asyncio
+    async def test_steps_activate_in_order(self, db: AsyncSession):
+        mandate = await _mk_mandate(
+            db,
+            steps=[
+                {"step_type": "formulation", "status": "pending"},
+                {"step_type": "candidacy", "status": "pending"},
+                {"step_type": "vote", "status": "pending"},
+            ],
+        )
+
+        # Advance 1: activates step 0, moves to candidacy
+        await advance_mandate(mandate.id, db)
+        loaded = await _reload(db, mandate.id)
+        assert loaded.status == "candidacy"
+        assert loaded.steps[0].status == "active"
+        assert loaded.steps[1].status == "pending"
+
+        # Advance 2: step 0 → completed, step 1 → active
+        await advance_mandate(mandate.id, db)
+        loaded = await _reload(db, mandate.id)
+        assert loaded.steps[0].status == "completed"
+        assert loaded.steps[1].status == "active"
+
+        # Advance 3: step 1 → completed, step 2 → active
+        await advance_mandate(mandate.id, db)
+        loaded = await _reload(db, mandate.id)
+        assert loaded.steps[1].status == "completed"
+        assert loaded.steps[2].status == "active"
+
+        # Advance 4: step 2 → completed, no more pending → advance mandate status
+        await advance_mandate(mandate.id, db)
+        loaded = await _reload(db, mandate.id)
+        assert loaded.steps[2].status == "completed"
+        assert loaded.status == "voting"
+
+    @pytest.mark.asyncio
+    async def test_advance_terminal_raises(self, db: AsyncSession):
+        for terminal in ("completed", "revoked"):
+            mandate = await _mk_mandate(db, status=terminal)
+            with pytest.raises(ValueError, match="statut terminal"):
+                await advance_mandate(mandate.id, db)
+
+
+# ---------------------------------------------------------------------------
+# TestMandateRevocation
+# ---------------------------------------------------------------------------
+
+
+class TestMandateRevocation:
+    """revoke_mandate: active/pending steps cancelled, completed steps preserved."""
+
+    @pytest.mark.asyncio
+    async def test_revoke_cancels_active_and_pending(self, db: AsyncSession):
+        mandate = await _mk_mandate(
+            db,
+            status="active",
+            steps=[
+                {"step_type": "formulation", "status": "completed"},
+                {"step_type": "assignment", "status": "active"},
+                {"step_type": "reporting", "status": "pending"},
+            ],
+        )
+
+        await revoke_mandate(mandate.id, db)
+
+        loaded = await _reload(db, mandate.id)
+        assert loaded.status == "revoked"
+        assert loaded.ends_at is not None
+        assert loaded.steps[0].status == "completed"
+        assert loaded.steps[1].status == "cancelled"
+        assert loaded.steps[2].status == "cancelled"
+
+    @pytest.mark.asyncio
+    async def test_revoke_sets_ends_at(self, db: AsyncSession):
+        mandate = await _mk_mandate(db, status="draft")
+
+        await revoke_mandate(mandate.id, db)
+
+        loaded = await _reload(db, mandate.id)
+        assert loaded.ends_at is not None
+
+    @pytest.mark.asyncio
+    async def test_revoke_already_revoked_raises(self, db: AsyncSession):
+        mandate = await _mk_mandate(db, status="revoked")
+
+        with pytest.raises(ValueError, match="statut terminal"):
+            await revoke_mandate(mandate.id, db)
+
+
+# ---------------------------------------------------------------------------
+# TestNominationInteractions
+# ---------------------------------------------------------------------------
+
+
+class TestNominationInteractions:
+    """Cross-process: nomination + assignment + lifecycle are consistent."""
+
+    @pytest.mark.asyncio
+    async def test_assign_then_advance_full_cycle(self, db: AsyncSession):
+        """Assigning a mandatee then running the full lifecycle completes cleanly."""
+        mandatee = await _mk_identity(db, "Isabelle")
+        mandate = await _mk_mandate(
+            db,
+            steps=[
+                {"step_type": "formulation", "status": "pending"},
+                {"step_type": "assignment", "status": "pending"},
+                {"step_type": "completion", "status": "pending"},
+            ],
+        )
+
+        # Assign before starting
+        await assign_mandatee(mandate.id, mandatee.id, db)
+
+        # Run through all steps
+        for _ in range(5):
+            m = await advance_mandate(mandate.id, db)
+            if m.status in ("completed", "revoked"):
+                break
+
+        loaded = await _reload(db, mandate.id)
+        # All steps completed, mandate advanced beyond steps
+        assert all(s.status == "completed" for s in loaded.steps)
+        assert loaded.mandatee_id == mandatee.id
+
+    @pytest.mark.asyncio
+    async def test_revoke_after_assign_preserves_mandatee_id(self, db: AsyncSession):
+        """Revoking a mandate keeps mandatee_id (for audit trail)."""
+        mandatee = await _mk_identity(db, "Jacques")
+        mandate = await _mk_mandate(db, mandatee_id=mandatee.id, status="active")
+
+        await revoke_mandate(mandate.id, db)
+
+        loaded = await _reload(db, mandate.id)
+        assert loaded.status == "revoked"
+        assert loaded.mandatee_id == mandatee.id
+
+    @pytest.mark.asyncio
+    async def test_origin_and_mandatee_can_differ(self, db: AsyncSession):
+        """The person who proposed the mandate (origin) is different from the mandatee."""
+        proposer = await _mk_identity(db, "Kim")
+        mandatee = await _mk_identity(db, "Laurent")
+
+        mandate = await _mk_mandate(db, origin_id=proposer.id)
+        await assign_mandatee(mandate.id, mandatee.id, db)
+
+        loaded = await _reload(db, mandate.id)
+        assert loaded.origin_id == proposer.id
+        assert loaded.mandatee_id == mandatee.id
+        assert loaded.origin_display_name == "Kim"
+        assert loaded.mandatee_display_name == "Laurent"